My girlfriend finished getting all of the achievements required for the mounts just before servers went down for 5.1, expecting to be able to claim 2 of the 3 remaining mounts she needed after servers went up again. She had the achievements and the equipment would be re-obtainable to those of us who had the achievements, so it makes sense, right?

She logged in to find that she couldn't claim her horse mounts despite having the achievements. Similarly, she also has a Whisper-a-Go-Go, and that still appears with Jonathas since she has the required Achievement, but the Garo mounts are nowhere to be found. She contacted a GM and they informed her that she had to claim them before the 5.1 patch came up.

Why is it this way for the Garo mounts, yet people can still claim Whisper-a-Go-Go? Whatever the case, something's wonky and there is no standardization between which rewards based on 3rd-Party Properties stay and which go.