ARM-based Chromebook (SNOW revision 4) won't get past usb boot

Hi, I’ve been messing with the chromebook (SNOW) as said in the title, trying to get PostmarketOS and/or Arch Linux ARM to boot on the chromebook.

Some important notes you might need to know:

I’ve looked at the resources described above, and what it seems to boil down to is to get the chromebook into developer mode, enabling usb boot and stuff with crossystem, optionally setting GBB flags, and then using CTRL+U to boot to the usb as stuff like legacy boot doesn’t seem to be supported on the ARM-based chromebooks in question, at least from what I’ve read and seen.

Is there any details I’ve missed? Regardless of which images I’ve used they all seem to result in the screen going black for a second or two, then beeping. I’ve been stuck at this step for a minute and I need some insight on what I could possibly do here. Thank you!

Edit: I solved the issue, apparently the issue was the SD cards and drives I used. I used an (older) Samsung 32 GB SD card and that “just worked”.

Also, you should consider using pmbootstrap instead of flashing an image.