Disclaimer: By attempting any of the processes listed in this thread you accept full responsibility for your actions. I will not be held responsible if your device stops working, catches fire, or turns into a hipster and claims to have been modified before it was cool.
Hi everyone, similar to my threads for OP3, OP3T, OP5, OP5T and OP6 as unbrick tools allow to (obviously) unbrick your phone but also to rollback to specific versions of Oxygen OS I decided to search for more and succeeded in that.
As the instructions and Qualcomm drivers are already available here , I don't feel a need to rewrite them.
You can ask questions here on how to use and issues, however I might not be able to answer immediately.
Here are the files uploaded on AndroidFileHost ordered by Android version:
According to@fullofhell , the commands "fastboot erase modemst1" and "fastboot erase modemst2" will turn off SIM lock definitely and allow OEM unlock option to stop being greyed out in developer options (behaviour introduced in OOS versions superior to 9.0.11). That will allow to unlock bootloader and then root/flash custom roms.
As a reminder, it is not possible for anyone besides OnePlus to generate EDL packages: I just get the files and reupload them whenever I have time. Posting latest version is just a convenience, you don't need it specifically to recover your device.