created 500gb volume, mapped, formatted and put some files.
created 250gb snapvol, associated it with the 500gb vol.
delete the 250gb snapvol and i get same error(below).
also noticed this:
create 500gb volume, map
create 250gb snapvol, associate with 500gb volume.
try to format the 500gb volume and fail - same event(below)
delete the 250gb snapshot volume
try to format the 500gb volume and it works!
now i can create the snapvol and associate it without error.