The FE that rewards the Ambassador could also be part of the 3rd Year Anniversary. In fact, it's very likely what the 3rd Year Anniversary will be centered around.
Not going to rule it out, but I'm really not expecting it.
The First Anniversary was just Q appearing and us fishing for goodies (literally).
The Second Anniversary was basically the same, with Q appearing and giving away gifts. And Cryptic throwing together a quick mission for the Free Odyssey / Bortas which took us to Mars Orbit / Gandala Orbit and giving the U.S.S. Odyssey / I.K.S. Bortas her shakedown cruise.
They said they wanted it as a Featured Event, which is a 5-mission story arc. So if they don't do it, it would somewhat be a disappointment.
If indeed that the new FE special rewards will be the Ambassador Enterprise C, I hope it remains as a special reward long after the anniversary is over.
I would like to reclaim the vessel at any time.
However; truth be told, I prefer the ship to be offered at the CStore. So in a way, I really am hoping that the Ambassador Class is NOT offered as a anniversary gift, which could mean reclaiming it afterwards may not be possible.
Just like with the Odyssey, I'm guessing the free version you can get will only be T4 and there'll be a 10 console slot T5+ version in the C-Store soon after. I see the free version more as a tease. I'm not in the market for cruisers anyway, I'll just collect it on a character or two and that'll be it. I doubt I'll ever actually fly one if it's an Ambassador. I'm looking forward more to my free Chel Grett.