If planefags thread isn't already logging flights, it needs to start logging amounts of flights into/out of GITMO if possible. Nice catch, keep it up…
Good to hear. Please organize your fellow planefags, so this stuff can be tracked. Your C-40, C-32 assumptions are good and I would track as well. What they are carrying, detainees, troops (engineers, guards, etc), or cargo is the question. Tracking where flights leave from and what types of flights came into that airfield prior, may give you clues as to what the cargo might be.
Once you have developed a pattern, put together informational meme that explains the departure fields and what you believe they might mean so that others can learn and assist with tracking (ex: What you mentioned…regularly scheduled flights from FLA = Cargo)
The graphical evidence is a good part of the tracking too.
Keep up the good fight.