Cannot resize APFS volume after installing Big Sur

[tomadimitrie]

Hi, I've installed Big Sur beta 2 and tried to use Boot Camp Assistant but I got the error "disk could not be partitioned". Also tried to partition manually but "a problem occurred while resizing APFS container structures". I don't use Time Machine but there were 3 snapshots starting with com.apple.os.update- that can't be deleted. I ran First Aid and fsck_apfs and no problem was found. Any other thing to try? Thanks!

 

[tomadimitrie]

Finally found a fix! Deleting snapshots using `tmutil` didn't work but I deleted them with `diskutil` from Recovery: `diskutil apfs listSnapshots <Macintosh HD's disk id>` and then `diskutil apfs deleteSnapshot <disk id> -uuid <snapshot uuid from the previous command>` for every snapshot. I had 3, two of them were deleted and one returned "insufficient privileges" but it doesn't matter, now everything works. Do it at your own risk, I don't know whether it will work on your Mac.