Pixel XL v.1 Verizon model, unlocked bootloader (when you could still do it in 2018), Magisk rooted, TWRP 3.3.0-0, Factory/OTA 8.1 loaded from within TWRP.
Have been asked to upgrade to Factory/OTA 10 without losing unlocked & root status and keep all apps/data, just upgrade the OS. This has previously been done from 8.1 to 9.0 from within TWRP and back to 8.1, no problem.
Is Factory/OTA 10 different? Would I simply download TWRP 3.4 and Factory/OTA 10 to the Pixel XL, reboot to TWRP, install new TWRP from within current TWRP, reboot to new TWRP and install factory/OTA 10? Need to upgrade to 9.0 first?
I have tried a complete backup from within TWRP, but it hangs at the very end and does not complete. I have read that it is an issue with Pixel XL.