If it is called 2.1.something it will be emc2. BDI and emc2 have become different branches of the original emc project. Or maybe more correctly, emc2 is the main emc project and BDI has branched off.I think I'm running EMC 2.1.16, whatever came on the BDI.
edit: Double checking the information, it is possible to have a BDI version 2.1.something. It would be a bit old at this point as the branching of the projects is not a recent event. The story of the EMC/BDI split is a bit sad really.