I'm sure I read on this very forum board that a former CAS (Craig?) had barely 1000hrs in his log book.
Edit - see this
link, my error - it appears Craig tried to get 1000 hours in a two year tour (I assume as it was a 'PN' post it was when a Vulcan CO) but mention is made of a different CAS with <1500hrs total (presumably after a minimum of flying training, a junta tour, flt cdr tour, sqn cdr tour plus the odd hour as a stn cdr). Still not much given the hours that were available 'way back then'!