Device: OnePlus 7T (Hotdogb)
Recommended Recovery: https://sourceforge.net/projects/infinity-x/files/hotdogb/16/gapps/recovery/recovery_v3.1.img/download

dtbo.img: https://sourceforge.net/projects/infinity-x/files/hotdogb/16/gapps/extras/dtbo_v3.1.img/download
vbmeta.img: https://sourceforge.net/projects/infinity-x/files/hotdogb/16/gapps/extras/vbmeta_v3.1.img/download

Flashing Instructions:

Be on OOS12

* Clean Flash:

1. Reboot to bootloader
2. fastboot flash vbmeta_a vbmeta.img && fastboot flash vbmeta_b vbmeta.img
3. fastboot flash dtbo_a dtbo.img && fastboot flash dtbo_b dtbo.img
4. fastboot flash recovery_a recovery.img && fastboot flash recovery_b recovery.img
5. Reboot to recovery
6. Format Data
7. Apply update -> adb sideload
8. adb sideload rom.zip
9. Reboot

* Dirty Flash:
1. Reboot to recovery
2. Apply update -> adb sideload
3. adb sideload rom.zip
4. Reboot

* OTA:
1. Simply upgrade via ota updater (either if pushed or via local update import)