Android Q

This is the original SPL which is installed in a stock G1. It is easily distinguished by the “trademark” red-green-blue bootloader screen which appears in many HTC phones. This SPL does not support the fastboot protocol and thus will not allow the user to flash nand backup images. Use this SPL to restore your phone [...]

Okay, for some reason you want to unroot your phone or bring it back to stock. This is useful if you no longer like custom ROM’s or need to send your phone in for warranty purposes.
This process will take you down to a stock firmware of RC29. If you just leave the phone on, you [...]