So, senility check:
According to Bronnenkant PlM vol 1 (a must if you are interested in Boelcke & Immelmann) the original complement at Velú in Sept '16 -- when Jasta 2 started operations-- were a single Fokker D.III (352/16), a Fokker D.I(!) and an Albatros D.I which was brought over by a transferring pilot from Jasta 1. Boelcke is thought to have flown all three on operations. The two Fokkers arrived on Sept 1, it's unclear when the transferred Alb D.I arrived; the factory deliveries of Albatros D types (I & II simultaneously
) commenced on Sept 16.
Besides 352/16, there is a series of photos of Boelcke sitting in an unarmed D.III, apparently at Schwerin. This aircraft possibly became 350/16 which a number of well-known photos exist in military configuration.