I seem to remember the figure of 20 tons for senior comm. Those were the days, hey Swanepoel!!!!
Having flown 6000 hours on the KingAir on contract, I did complete the last 800 hours on the B1900 UC (long range tanks), and remember that we were not allowed to treat it, as single crew in East Africa. Strictly 2 crew only, regardless of the POH limitations/certification. (rules is rules!) When training was being undertaken, or when I was doing the type rating testing for the Kenyan DCA, we had to carry a qualified P2 in the back, so in the end were actually 3 crew.
Now as for logging of hours with 3 crew in a B1900, this leaves another question.
Mind you, I last flew this aircraft over 10 years ago before joing the airline world, so a lot has been forgotten and so I find this thread most interesting.
I still hold a P2 on the machine with a SA ATPL, but have never utilised the SA ALTP ever since obtaining it, and never completed a P1 check ride in SA, only in East Africa.