You know where this is going. I'm guessing that in the new movie,from what I've seen, the Enterprise "unit patch" is being used as the Starfleet symbol in this movie. This has always irritated me. What did the Enterprise do that was so special that Starfleet adopted it for the entire service?
The way I'm retconing it, is that the delta symbol was the general symbol for Starfleet, not something unique to the Enterprise. Other ships that had different symbols were part of different specialized task forces. There is no on screen evidence to indicate any of this but it works in my mind *shrug*
Yeah, my personal theory has always been something along those lines too.
Makes more sense if the delta/arrow was *always* the Starfleet symbol, and various ships/starbases/stations/etc had there own individual emblems - but some - like the Enterprise, being the "flagship" - the crew wore the Starfleet symbol. (Captain's discretion, maybe?)