What's the difference between the bootloader shipped with XIAO BLE and Adafruit's NRF52 bootloader?

I know they are compatible because the flashing step in the Arduino IDE uses the adafruit-nrfutil command. However, there’s currently no support for the Xiao BLE/BLE Sense in the upstream project.

I’d prefer to flash my own bootloader, but i don’t wanna screw it up.

So are there any differences between the upstream version and the one onboard other than lack of upstream contribution of the proper board file?

I would appreciate if you folks would contribute your changes to the upstream project.

Also, the default offset is different: 0x27000 instead of 0x26000 for the application start area. Why is that? is it just to leave room for say device stored settings?

I think i finally found the source here: GitHub - 0hotpotman0/Adafruit_nRF52_Bootloader: USB-enabled bootloaders for the nRF52 BLE SoC chips