Develop Bugs

Does rooting only removes the ability for OTA updates?

Hey guys just received my n7 yesterday and am very pleased with this, however I have some questions.
Does rooting (only) removes your OTA updates access? I also own a Galaxy S4 (rooted) and I can't get OTA, it says it's modified, but I did flash a custom update on it and kernel. So if I just root my n7, and not flash anything, I will still get OTA's correct? I just want to use some apps which requires root access and not planning to flash a custom rooms or anything. Thanks for any help.
Sent from my Nexus 7 using Tapatalk 4

Mine is always rooted, and I get all OTAs.
Sent from my Nexus 7 using xda app-developers app

You just need to have the stock recovery to receive OTAs.

Username invalid said:
You just need to have the stock recovery to receive OTAs.
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Click to collapse
So if I have twrp installed, i won't receive them?
Sent from my Nexus 7 using Tapatalk 4

Takes 10 seconds to reflash the stock recovery.

UPDATE: SuperSU-v1.55 added the fix for the OTA update issue, so this post is no longer necessary unless you are using an older version of SuperSU
This post also applies to JSS15Q update.
I actually went through and tested JWR66N rooted with SuperSU and the JSS15J OTA update. I expected it to work but it exited with an error.
Ironically the JSS15J OTA actually did patch every single file successfully but near the end while setting permissions, it came up with an error, so after reboot you'll actually be running with all JSS15J rom files, except your build will still say JWR66N, you'll still be running the JWR66N recovery, and you'll still be running the 3.05 bootloader.
I tracked down the issue and put together a fix for it. If you want, it is attached to this post. You just run it after installing SuperSU, so basically:
adb reboot bootloader
fastboot boot twrp.img
within TWRP
install UPDATE-SuperSU-v1.51.zip (SuperSU v1.55 or greater incorporates the OTA fix)
install UPDATE-SuperSU-v1.55.zip
install UPDATE-SuperSU-ota.zip (can be chain installed, just make sure you choose to install it 2nd)
reboot
You'll need to redo these steps (both the installs) after you receive the OTA to preserve root and ability to receive future OTAs.
Also as others have mentioned it is best to be running stock recovery (which the above commands will allow you to do because twrp is never flashed on the tablet) I've attached the stock recovery for JSS15J in case someone needs it.
If you make ANY modifications or delete files from the stock ROM with your new root privileges, then you will greatly increase the chances of the OTA failing. Adding new files is normally fine.

Well shoot - now you have me worried. I did install TWRP, but never considered that would block OTAs. Do they attempt to install and fail?
Sent from my Nexus 7 using xda app-developers app

rmm200 said:
Well shoot - now you have me worried. I did install TWRP, but never considered that would block OTAs. Do they attempt to install and fail?
Click to expand...
Click to collapse
On some platforms, especially when flashing bootloaders and/or radios, the stock recovery pulls some funky maneuvers to get that done. Often custom recoveries are not privy to those maneuvers. Also sometimes custom recoveries will experiment with custom kernels which don't always have the bootloader and/or radio devices mapped the same as the stock kernel. This can lead to problems to.
Thus it is safest to use stock recovery to flash OTAs.
I have flashed the complete JSS15J OTA except for the bootloader part using TWRP and it works ok. All the ROM files are patched.
I just didn't feel like risking my tablet with the bootloader flash portion of JSS15J OTA using twrp. It might work fine. I just know from the past the potential for issues are higher in that section of the OTA flash.

Is it common for nice folk on here to upload a stock zip of say for example, 4.3.1 when it releases so that we can flash it through a custom recovery (e.g., TWRP, CWM etc.), without having to change our custom recoveries?

It was common on other platforms I've used, but I don't know about here.

Root will not prevent an OTA update from coming in and installing, and a custom recovery won't "block" (it just won't be able to complete the install of it automatically). I have been installing OTA updates on rooted Nexus devices with custom recoveries since the Nexus One, and assuming the new Nexus 7 works the same way, the following applies:
If you are running stock ROM, your deivce will receive the notification and download the update, even if rooted
If you are running stock recovery, the update will install automatically as normal
If you are running a custom recovery like CWM or TWRP, it will fail to install automatically but it will still have downloaded to the device and you can use the custom recovery to install it yourself (I've never had this fail)
If you have modified files in /system, the OTA update is pretty much guaranteed to fail regardless of which recovery you use
If you successfully install the OTA update, you will no longer have root, so flash SuperSU using a custom recovery after the OTA update installs
Also:
You can always look for the OTA zip URLs on XDA and just download the update yourself to flash if you don't want to wait for it to come to your device (this is what I always do)
You can flash factory images instead of the update, without losing data (see other threads for how)
If you want to keep stock recovery installed, you can always use fastboot to boot a custom recovery without flashing it, in case you ever need it
The above is accurate and correct as far as I'm aware from my own experience over the years with Nexus devices. I'm sure someone will be happy to correct me if anything is wrong Hope this helps.

phazerorg said:
Root will not prevent an OTA update from coming in and installing, and a custom recovery won't "block" (it just won't be able to complete the install of it automatically).
Click to expand...
Click to collapse
I thought the same about root not blocking the OTA update install from being successful, but that was with years of using superuser.
With SuperSU (I am not sure which version introduced it) they set the immutable flag on a file in almost every OTA. I believe this is to support some OTA survival mode. This causes the OTA to fail in the section where it sets permissions. All the files are patched at that point, but the build.prop hasn't been modified to reflect the new version # and the bootloader and recovery haven't been flash.
You'll essentially be running JSS15J but your software will report it is on JWR66N, your bootloader wouldn't have been patched, and you would be running JWR66N recovery.

TheAltruistic said:
Is it common for nice folk on here to upload a stock zip of say for example, 4.3.1 when it releases so that we can flash it through a custom recovery (e.g., TWRP, CWM etc.), without having to change our custom recoveries?
Click to expand...
Click to collapse
yes the ota update zip always gets posted so you can manually flash with a custom recovery...
just keep in mind you need to keep your files stock otherwise it might not work
Sent from my Nexus 7 2

nolook said:
yes the ota update zip always gets posted so you can manually flash with a custom recovery...
just keep in mind you need to keep your files stock otherwise it might not work
Sent from my Nexus 7 2
Click to expand...
Click to collapse
When you say keep your files stock what does that mean exactly? I have titanium backup app installed would that be one of them? Thanks.

Mightym83 said:
When you say keep your files stock what does that mean exactly? I have titanium backup app installed would that be one of them? Thanks.
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Titanium backup is an app, I assume with files he is targeting e. G. Config files.
Sent from my Nexus 7 (2013)

Mightym83 said:
When you say keep your files stock what does that mean exactly? I have titanium backup app installed would that be one of them? Thanks.
Click to expand...
Click to collapse
It means don't modify or delete any files in /system
Don't remove a system app that shipped with the tablet. You can install a new version as that just hides the one in /system, but if you remove or modify the original, then the OTA will very likely fail (depending on how complex the OTA is)
Adding files is ok.

Alright, so here's my scenario. Hopefully someone can tell me what should happen:
I am running the stock ROM on my Nexus 7 (2013), but I have ClockWorkMod Recovery installed and I'm using Koush's Superuser app for root permissions. The only system file that I think I have changed is my hosts file because of Adaway. That is easily reverted, though.
So can I just download the OTA, install it manually from the custom recovery (flashing the update.zip file), and then re-flash Koush's superuser app back onto the device?
Will that go smoothly, and will the newer build number be accurately reflected in my About Phone afterward?
(that last part is just my OCD talking)

phazerorg said:
:
[*]If you are running a custom recovery like CWM or TWRP, it will fail to install automatically but it will still have downloaded to the device and you can use the custom recovery to install it yourself (I've never had this fail)
Click to expand...
Click to collapse
This was very helpful, and this is the category i fall in. However, i have installed a kernel. does that change anything?
So basically what you are saying is this, with my current set up:
1 - i will get the update, it will download, but wont install. I should boot into TWRP and install the file that way. Correct? Where is the downloaded file stores?
2 - I can just wait for the download to be posted on here, and just install via twrp.
3 - either way, after installing it, i will lose root. I should then boot into twrp and flash supersu.
Correct?

Theoretically it could work. I believe the flash has worked with twrp.
Personally I always put stock recovery back to flash ota's though especially if there is a bootloader (or radio if you have a mobile version) because on some platforms they involve special procedures that may not be in the custom recovery.
On nexus it looks like it will work with custom recovery but it takes so little effort to put stock recovery back I just do it automatically.
Having said that, I've seen one person post it worked on twrp but haven't read an experience on cwm. Not saying it will or won't work.

If we are running the stock ROM, but have it rooted with the custom recovery, why cant we just use Wegfresh's nexus toolkit to Unroot and image using the updated IMG file?
Then go through and use it to recreate the root\custom recovery again?

To root the nexus 5x or to not root

Hey, I opened my new nexus 5x a couple days ago and it's been running great. However, I came from an htc one m7 that was rooted and had greenify auto hibernation thing. So, I sorta feel like rooting just for the greenify auto hibernation feature.
The reason why I don't feel like rooting this is because I spend too much time on upgrading (to new versions of a rom, and having to redownload everything over). Do you guys think it's worth rooting? How do you deal with updates of a rom?
If I root, I would just stick to one rom (the most stable one and wait for updates on that I guess, since updates to a rom don't require clean install of rom)

Like you I came from rooted M7 (running ARHD) . I did not even unlock the bootloader on my 5X.. and am quite satisfied.

Either way, you should unlock your bootloader. It is far easier to resolve any issues with your bootloader unlocked.
Sent from my Nexus 5X using Tapatalk

SlimSnoopOS said:
Either way, you should unlock your bootloader. It is far easier to resolve any issues with your bootloader unlocked.
Sent from my Nexus 5X using Tapatalk
Click to expand...
Click to collapse
Not to mention, unlocking requires a complete wipe... Might as well get that out of the way
Sent from my Nexus 5X using Tapatalk

so wait, unlock bootloader, as in I should root my phone?

Unlocking bootloader just unlocks it, it doesn't do anything other.
You can decide then if you want to root or not, but it would be wise to unlock it anyway if you ever change your mind because your phone is completely wiped when you unlock it, so it better be the first thing you do with your phone...
You can use the guide here to unlock it
https://developers.google.com/android/nexus/images?hl=en
If you do decide to root, to upgrade to a new version you just flash it manually without wiping your data, so you don't need to reinstall anything. And after that just re-root, and that's it...

As mentioned above as long as you stick with one rom you dont need to wipe internal storage with each update (usually data, system and cache) if that and reinstall su as current versions of superuser dont modify the the system partition.
Root gives more freedom with your phone easy backups with titanium and potentially better battery life or a rom more suited to your needs.
Sent from my Nexus 5X using Tapatalk

The_Automator said:
As mentioned above as long as you stick with one rom you dont need to wipe internal storage with each update (usually data, system and cache) if that and reinstall su as current versions of superuser dont modify the the system partition.
Root gives more freedom with your phone easy backups with titanium and potentially better battery life or a rom more suited to your needs.
Sent from my Nexus 5X using Tapatalk
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Click to collapse
Oh ok. I went to check out the Nexus 5x Android development thread and saw the stock rom of the new 6.0.1 update. But then, i saw someone on the comments asking if they had to flash the radios or something on post #5: http://forum.xda-developers.com/nexus-5x/development/rom-nexus-5x-stock-rom-t3267096
and the guy said, "Yeah, you need the bootloader, radio, vendor images. It's probably easier to just flash 6.0.1 from here https://developers.google.com/androi...mages#bullhead"
so everytime a new version comes out of stock, i need to flash the bootloader, radio, and vendor images?
What if I'm not on stock rom and on a custom rom, then everything will be included in the rom zip file i assume (i just flash the rom, and that's it)?

theBhav007 said:
Oh ok. I went to check out the Nexus 5x Android development thread and saw the stock rom of the new 6.0.1 update. But then, i saw someone on the comments asking if they had to flash the radios or something on post #5: http://forum.xda-developers.com/nexus-5x/development/rom-nexus-5x-stock-rom-t3267096
and the guy said, "Yeah, you need the bootloader, radio, vendor images. It's probably easier to just flash 6.0.1 from here https://developers.google.com/androi...mages#bullhead"
so everytime a new version comes out of stock, i need to flash the bootloader, radio, and vendor images?
What if I'm not on stock rom and on a custom rom, then everything will be included in the rom zip file i assume (i just flash the rom, and that's it)?
Click to expand...
Click to collapse
Custom roms usually dont include radio vendor or bootloader these are flashed from fastboot as opposed to recovery. Custom roms from what I understand mostly modify the system partition. Each thread for the roma tends to have great support. Im currently on uber rom
Sent from my Nexus 5X using Tapatalk

The_Automator said:
Custom roms usually dont include radio vendor or bootloader these are flashed from fastboot as opposed to recovery. Custom roms from what I understand mostly modify the system partition. Each thread for the roma tends to have great support. Im currently on uber rom
Sent from my Nexus 5X using Tapatalk
Click to expand...
Click to collapse
you can use Nexus root toolkit. all with one click, only what I don't like is the message that appears "we can't control if your device is corrupt".
Is there anybody who know how to prevent that message?
Rooting with this is a piece of cake.
I unroot my new nexus 5 because of the message.

Using Flashfire?

I downloaded Chainfire's Flashfire app now that it is live on the Play Store. I had been updating firmware as separate files (system.img, vendor.img, boot.img all separately) using fastboot and may continue to do so at the monthly updates, but I wanted to check and see if anyone reported any problems or successes using the app.
My N5X is unlocked and rooted, running stock firmware with the exception of a custom recovery (TWRP) and custom kernel (ElementalX).
Here is my question: Would the process of updating via FlashFire be to let it install the new firmware once binaries are released, keep root, and just flash the kernel and other zips (like AdAway, Viper4Android) once it's done?
Just trying to get some advice on whether FlashFire is that much more convenient than just using fastboot and flashing firmware manually. Any experiential responses would be appreciated.

When an update comes out just sideload the ota in recovery. Twrp works as well as stock. You'll get the latest firmware and you don't lose data. Download the ota from the same site as the factory image are, https://developers.google.com/android/nexus/images
Sent from my Nexus 9 using XDA Free mobile app

Flashfire is safe to use. But it is advised to update the bootloader via fastboot since it is much more secure, but I have updated it with Flashfire once and had no issues. As long you know what you are flashing, you won't have any problem. I've not used FF to flash OTA since I was always on a custom ROM, but what you describe sounds like something Flashfire was meant to do. You'll find more information in Chainfire's thread.

roofrider said:
Flashfire is safe to use. But it is advised to update the bootloader via fastboot since it is much more secure, but I have updated it with Flashfire once and had no issues. As long you know what you are flashing, you won't have any problem. I've not used FF to flash OTA since I was always on a custom ROM, but what you describe sounds like something Flashfire was meant to do. You'll find more information in Chainfire's thread.
Click to expand...
Click to collapse
I see that you've flashed the bootloader with FlashFire on your Nexus 5X and had no issues. Did you use bootloader IMG file from Bullhead Official Images? Could you elaborate a little more about what specifically did you do to flash the bootloader with FlashFire?
I've a 5X with a dead USB port, so I'm highly interested on knowing the details

mishamosher said:
I see that you've flashed the bootloader with FlashFire on your Nexus 5X and had no issues. Did you use bootloader IMG file from Bullhead Official Images? Could you elaborate a little more about what specifically did you do to flash the bootloader with FlashFire?
I've a 5X with a dead USB port, so I'm highly interested on knowing the details
Click to expand...
Click to collapse
I've not used FlashFire lately, but it was pretty straightforward. Yes I used the bootloader IMG file, but probably downloaded from Flash's or Bean's file host. Just enable Bootloader flashing in FF's settings, add the Firmware package (bootloader image), select the partition, and Flash. Though it works, it's not the safest way to flash bootloaders. I would suggest checking FF's thread just to make sure the app supports the latest bootloader update and whatnot. It being Chainfire's app there should be no reason to worry, but always a good idea to read/search the official thread in such cases.

Keep Magisk/Root and Take Updates?

On OG Pixel XL, I used to be able to follow this guide to take OTA updates and retain Magisk/root:
https://github.com/topjohnwu/Magisk/blob/master/docs/tips.md
It was the BEST! Super quick, small delta file download, one reboot and DONE. No PC needed, no full system image (1.6GB) download required.
But it hasn't worked with Pixel 2 XL (or maybe it's Magisk 15.x that broke this process?). Now any time I try this I get boot loops and end up having to download the full system image, flash-all.bat (remove -w) and then copy the boot.img, patch it in Magisk, and reflash via fastboot. I'd really love a way to be able to take OTA updates without having to get to a PC.
Is there an easier way?
I should mention the ONLY reason I use Magisk is to hide the fact I have an unlocked bootloader and allow things like Android Pay/Samsung Pay (which is broken with latest update anyway - detects Magisk). Any recommendations?

wy1d said:
On OG Pixel XL, I used to be able to follow this guide to take OTA updates and retain Magisk/root:
https://github.com/topjohnwu/Magisk/blob/master/docs/tips.md
It was the BEST! Super quick, small delta file download, one reboot and DONE. No PC needed, no full system image (1.6GB) download required.
But it hasn't worked with Pixel 2 XL (or maybe it's Magisk 15.x that broke this process?). Now any time I try this I get boot loops and end up having to download the full system image, flash-all.bat (remove -w) and then copy the boot.img, patch it in Magisk, and reflash via fastboot. I'd really love a way to be able to take OTA updates without having to get to a PC.
Is there an easier way?
I should mention the ONLY reason I use Magisk is to hide the fact I have an unlocked bootloader and allow things like Android Pay/Samsung Pay (which is broken with latest update anyway - detects Magisk). Any recommendations?
Click to expand...
Click to collapse
I'm not sure about your way anymore cuz I always install it with TW RP but if you don't need root and you're just wanting to hide your unlocked Bootloader you can just flash a custom kernel and be done with it.

mac796 said:
I'm not sure about your way anymore cuz I always install it with TW RP but if you don't need root and you're just wanting to hide your unlocked Bootloader you can just flash a custom kernel and be done with it.
Click to expand...
Click to collapse
Hey! Thanks for the quick reply. Wouldn't flashing a custom kernel be the same cat and mouse since the OTA would flash a new kernel? I'd need to have a mechanism for flashing the kernel which I'm guessing means TWRP.
I always ran a custom recovery before Pixel so I'm familiar with TWRP but having a custom recovery means you can't take OTA. What is your process for flashing the updates in TWRP? I thought you had to have a flashable .zip file specifically meant to be flashed in a custom recovery. Are you now able to flash system images from there? Do you just reflash Magisk after each time? I'm guessing that means you have to download the full 1.6G image since Google doesn't post the delta file?
Sent from my Pixel 2 XL using Tapatalk

wy1d said:
Hey! Thanks for the quick reply. Wouldn't flashing a custom kernel be the same cat and mouse since the OTA would flash a new kernel? I'd need to have a mechanism for flashing the kernel which I'm guessing means TWRP.
I always ran a custom recovery before Pixel so I'm familiar with TWRP but having a custom recovery means you can't take OTA. What is your process for flashing the updates in TWRP? I thought you had to have a flashable .zip file specifically meant to be flashed in a custom recovery. Are you now able to flash system images from there? Do you just reflash Magisk after each time? I'm guessing that means you have to download the full 1.6G image since Google doesn't post the delta file?
Sent from my Pixel 2 XL using Tapatalk
Click to expand...
Click to collapse
I always Flash the factory image I don't take the OTA. And then I fastboot the TWRP boot image and then install the twrp zip. After that you'd Flash the magisk zip inside TWRP. But if you're just looking to hide the bootloader you can fastboot the custom kernel on stock with no root I Believe In The Flash thread he has both files the fastboot and the Zips for TWrp. But yeah every month you want to flash an updated kernel. Nate actually keeps up on the security updates so he has a new ones quite often.
Edit. Yes so if you wanted to take the OTA I believe you would have to flash the factory boot image to wipe out that kernel and then you could take the following months OTA

mac796 said:
I always Flash the factory image I don't take the OTA. And then I fastboot the TWRP boot image and then install the twrp zip. After that you'd Flash the magisk zip inside TWRP. But if you're just looking to hide the bootloader you can fastboot the custom kernel on stock with no root I Believe In The Flash thread he has both files the fastboot and the Zips for TWrp. But yeah every month you want to flash an updated kernel. Nate actually keeps up on the security updates so he has a new ones quite often.
Edit. Yes so if you wanted to take the OTA I believe you would have to flash the factory boot image to wipe out that kernel and then you could take the following months OTA
Click to expand...
Click to collapse
So you do the full download and flash it from your PC every month?
Sent from my Pixel 2 XL using Tapatalk

wy1d said:
So you do the full download and flash it from your PC every month?
Sent from my Pixel 2 XL using Tapatalk
Click to expand...
Click to collapse
Yeah that's how I do it I edit the flash all bat remove the - w
So it doesn't wipe your data. It's pretty much like taking the OTA the manual way. But if you don't want to do that. And just take the OTA and you installed TWRP or if you just installed a custom kernel with fastboot. You just fastboot Flash the boot image of the month you're on and then you should be able to take your new OTA. I'm fairly sure you can do it that way I haven't done it that way in a long time.

mac796 said:
Yeah that's how I do it I edit the flash all bat remove the - w
So it doesn't wipe your data. It's pretty much like taking the OTA the manual way. But if you don't want to do that. And just take the OTA and you installed TWRP or if you just installed a custom kernel with fastboot. You just fastboot Flash the boot image of the month you're on and then you should be able to take your new OTA. I'm fairly sure you can do it that way I haven't done it that way in a long time.
Click to expand...
Click to collapse
That really isn't any quicker than what I'm doing now. I was hoping for a way to do it without needing a PC and fastboot although it does sound like that might prevent having to download the whole factory image (assuming TWRP can extract / backup the stock boot image?).
Seems like Flashfire or something like that was able to do this before - flashing the new image without a PC.
Sent from my Pixel 2 XL using Tapatalk

wy1d said:
That really isn't any quicker than what I'm doing now. I was hoping for a way to do it without needing a PC and fastboot although it does sound like that might prevent having to download the whole factory image (assuming TWRP can extract / backup the stock boot image?).
Seems like Flashfire or something like that was able to do this before - flashing the new image without a PC.
Sent from my Pixel 2 XL using Tapatalk
Click to expand...
Click to collapse
I've always been told never install an OTA with Flashfire or TWRP, especially if it has a new updated bootloader. Because if something goes wrong you're done. But I know people do it all the time
There's even a warning in Flash fires directions about it

mac796 said:
I've always been told never install an OTA with Flashfire or TWRP, especially if it has a new updated bootloader. Because if something goes wrong you're done. But I know people do it all the time
There's even a warning in Flash fires directions about it
Click to expand...
Click to collapse
Such a bummer the Magisk method doesn't work anymore. It's definitely the safest and most graceful.
Sent from my Pixel 2 XL using Tapatalk

Ota update for pixel 2 xl with magisk and twrp already installed

I am sure this has been asked and answered 100 times but for the life of me I can't find a definite answer. I have a Pixel 2 XL and it is rooted and I have Magisk and TWRP installed on it. I want to be able to install the OTA for this month, but I do not want to lose anything on the phone. I also would rather not lose Magisk or TWRP. Normally on my android phones I use ROMs and can just update through TWRP, but I want to stay on stock because I don't want to lose Active Edge. So can someone please help me by giving me step by step instructions or point me to instructions that are simple to follow so I can take the OTA?
I really appreciate the help.

I was having the same problem and was helped by some of the members here.. Best way is to flash the firmware after removing the -w from the flash all file. Then flash twrp and magisk.
Ota

Thanks for your help. I will try that.

magicmaker said:
Thanks for your help. I will try that.
Click to expand...
Click to collapse
Here's a quick little guide I made for updating monthly factory images. Hopefully it'll help you out :good:

Sorta related...
Are there any ROMS that come rooted so I don't have to go through the monthly process of backup/unroot/update/root/restore?
Would love to just flash a ROM update and be done.

rank78 said:
Sorta related...
Are there any ROMS that come rooted so I don't have to go through the monthly process of backup/unroot/update/root/restore?
Would love to just flash a ROM update and be done.
Click to expand...
Click to collapse
Not that I'm aware of, but maybe some on the horizon...

Badger50 said:
Here's a quick little guide I made for updating monthly factory images. Hopefully it'll help you out :good:
Click to expand...
Click to collapse
Hi, quick question
I am only able to do them steps above if I have done 'fastboot unlock_critical'? I have only done 'fastboot unlock'
Also I would need to boot into TWRP and flash a kernel + magisk to retain root?

You have to issue the "fastboot unlock_critical" command in order for the bootloader to update, since the bootloader is included in both factory images and full OTAs. Speaking of full OTA's, one of our recognized developers, @elliwigy, revealed (thread here) that it is possible to flash a full OTA image through TWRP, which eliminates the need to open the factory image and remove the -w flag from the last line. Flashing the OTA works because TWRP doesn't check signatures like the stock recovery. You will lose both root and TWRP upon reboot however, so you will still need to connect to a PC in order to reinstall TWRP so you can subsequently replace the stock Kernel with the Flash Kernel and then root.
I can verify this works, as I tried it with the May update.