Andy. These are the recorded numbers for 109s, looks like 45 was a B, 46 was a C.....
http://equinoxe.dk/SCWaircraft/bf109.html
A few years ago Michael Payne (sadly no longer with us) wrote that 6-42 to 6-56 were B-2s to make up losses in 1./2. Staffeln in Dec. 1937 but that was some time ago and more research done since.
Regards
Nick