When I received Marseilles VS from Herman, I already had another plant called Marseilles, so to distinguish them, I added the initials to differentiate them. He later called it Marseilles Black to distinguish it from Marseilles White. So Marseilles VS, Marseilles Black VS, etc. are the same. Over that years I have collected many supposed duplicates of things, and each one gets some designator to distinguish trem from one another. So there are Celeste IS, JN, GM, SD, etc. They are not all "equal" so I keep them with their distinctive labels. Also, the initials are important to when you want to look at pix at Figs 4 Fun to see a specific fig.
Maryland Berry was supposedly a Brown Turkey, and was labeled Brown Turkey MD, having come from Maryland. It was clearly not BT and was a superior variety, so I renamed it Maryland Berry to preserve its origin and better describe it. Maryland Berry does NOT equal Marseilles VS.