Thank you very much for Developing /e/os for theOP13!
It is suggested to install latest stock firmware.
This comes with the Anti Rollback mechanism (ARB)
The current level is ARB = 1 to be safe.
Does the/e/os Rom comes with ARB Level =1 as well ?
Or is it more secure to stay with an older stock Rom?
(From XDA: “… the ColorOS 16.0.3.501 update introduces a hardware-level Anti-Rollback (ARB) mechanism.”)
Thank you
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I cannot answer the question directly. But the relevant date is the Security Patch Level (SPL). It can be found via “Settings”, “About this Phone”, “Android-Version”, Android Security Update”
/e/OS 3.6 A16 comes with a SPL March 1st, 2026. If your Stock ROM has a SPL “younger” than this, you should be careful. But I assume, your SPL should be dated before March 2026. In this case, I would not expect the ARB to take effect.
I found two Droidwin blog posts by Sadique Hassan on the subject. If one already had ARB 1 it seems that one should check the ARB Index of the downloaded ROM before proceeding.
You can only flash firmware with ARB ≥ your phone’s current ARB. So a phone with ARB 0 can use a firmware having ARB Index 0 or 1. But a phone with ARB 1 can only use a firmware with ARB 1 or higher, if it uses a firmware with ARB 0, then the device will be bricked.
Source:
Hi Intersting,
Did you try the installation in the end? I’m also hoping to put eOS on a new oneplus 13 and would appreciate anyone’s feedback on which version they flashed from/to.
I am a little concerned by the documentation saying
“If your device is currently using a newer or older version than the required version, please upgrade or downgrade to the required version before proceeding with your /e/OS installation.”
As (and maybe im wrong here), “downgrade” sounds like “roll-back” which, as you pointed out, sounds like a potentially phone bricking manouver.
Hi,
yes I installed the e os system and everything works fine!
I updated my OP13 before to Version 16 on stock Rom, but one version before the ARB =1.
Installation was describted very good.
Only problem was, that I had to update the ADB Tool before. My older version stocked in the end.
Glad to hear it worked out! 
And thanks for confirming what you did!
Just for completeness, did you flash e-3.6 (e-3.7 seems to have only been released on the 11th of April) and do you know if the /e/OS releases have/expect an ARB value of 0?
If so this implies: if a potential /e/OS user were to upgrade their devices to oxygen/Color OS ..3.50x (ARB=1) and then Flash the /e/OS packages they would permanently brick their devices.
If that’s correct there should probably be an explicit warning on the documentation page.
Once again thanks again for taking the time to share what you did! Will make it easier for me and others.
Hope you enjoy it!
Hi,
I flashed with e/os 3.6 und last week it updated to 3.7 via OTA.
I’m sorry, but I don’t know the verrsion of ARB, but lineage os switched as far as I know to ARB=1, so I guess e / os too, but I can’t confirm it
Hey again, no worries.
I downloaded the /e/OS 3.6 community build, unpacked it, used payload-dumper-go to extract the contents of payload.bin and then ARBExtract on the xbl_config.img file.
This told me e-3.6 was already on arb1, as you had expected.
As such, I guess we don’t currently need to worry about the arb level when flashing to eOS (assuming no upcoming release of Oxygen/ColorOS has arb2 or something higher) as long as one is aware and careful if you want to rollback to an earlier ROM. (I’m no expert though, so anyone reading this, please take with a pinch of salt and do your own research).
Think I’m feeling confident enough to try the flash to eOS now. Maybe I get an evening this week. Will report back. Thanks again!
By the way, thanks to abid for the link with the arbextract how to!
Okay, the install and boot into eOS worked! 
Here is the order I did things in in case anyone else is unsure.
But result is a phone with ARB1 fused.
So this was using a European Oneplus 13: CPH2653.
It came with Android 15 version 15.0.0.305(EX01).
After plugging in a sim and checking SMS and phone operations (plus wifi and bluetooth) I used the OxygenOS Update to go through these updates:
From here I installed e-3.7.1 (which also has Major Version 3, Minor Version 0, ARB 1 and security update April 2026.)
Note: the recovery zip on the download page did not contain the init_boot.img file. There is the instruction to download it from the LineageOS site for dodge… but I had no idea which version of LineageOS corresponded to which eOS release.
However, unpacking the OS .zip and using payload-dumper-go again you get all the recovery files too. (I used sha256sum to confirm all recovery files such as boot.img and vendor_boot.img where identical to those in the recovery zip) Thus I took the init_boot.img from the unpacked e-3.7.1-a16-20260416608883-community-dodge.zip).
One small scary issue: once starting to flash the actual OS via the /e/OS recovery app I got an error on the screen of my device: “ERROR: recovery: Open failed: /metadata/ota: No such file or directory” and it stays there for a looong time, but eventually reported “Install completed with status 0” and, after rebooting, it loaded into /e/OS.
Probably a lot of unnecessary information (and in the wrong place) but maybe it will easy the path of someone else.
Thanks again to all at /e/OS for making a privacy respecting OS available!
