Thanks for the reply and for showing your results, very appreciated.
That was one of my questions like many others that gets no official answers from seeeds!
If you look at my comment on this thread, I already have asked if we can use this file update-Seeed_XIAO_nRF52840_Sense_bootloader-0.6.1_nosd.uf2 and copy-paste to the sense-ble when it is in bootloader mode and shows as a USB drive in PC. If yes , still this brings some questions and concerns; e.g I see a nosd in the file name! what does it mean? what is this new uf2? does it have any limitation of its own? or it is just an upgrade?
Cheers,
PS.
If per wiki’s say upgrading needs to be done by a JLink Downloader, this is NOT an option, it is ridiculous to ask people to buy a $500 to change the bootloader of a $15 board.