Does 6.6 relock? I have seen conflicting reports, Colton, I believe suggested bootloader remains unlocked, I think your report was you were relocked but succesfully unlocked again.... What a pain this latest OTA turned out to be, glad I waited....
Bootloader is relocked, phone won't boot after applying OTA update until you unlock bootloader. If you have in the past unlocked your bootloader.
The new bootloader checks each partition, if any have been changed it blocks the phone from booting.
To get around this start phone press power and volume up, boot to selector choose fastboot then unlock bootloader, reboot your phone will then boot into recovery and format data, then phone can boot.
The sneaky part is you have to unlock the bootloader to boot, even though bootloader displays it's unlocked, and you lose your data cause data partition must be formatted, if you backed up your data via twrp to micro sdcard you can then reinstall your data so no problem, if no backup data is lost.
I have applied the update twice, once through stock recovery and once through twrp results are the same.
Twrp can install the OTA, just like the stock recovery can.
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