You mention often that 507B did not exist anymore and that 507B and 507A were identical.
Which colours were used for Dorsetshire's camouflage? Which medium grey was in use at that time? If it was a medium grey?
There is this file collecting information about Dorsetshire's camouflage indicating that the pattern shown in both books is not correct for May 1941 (p. 9):
There it is stated that the camouflage was likely added in Simonstown in March 1941.