Hard to say but I agree that a lot of people do seem to be getting them, I just got it myself on my 4th kill after reset. I'd say that now is definitely the time to go all out just in case.
I have to say, the relief is immense. I had 35 level 100+ toons that could run it that were slowly built up over the years with RAF and the pre-legion invasion event mainly for world boss farming. It took hours to get them all through yesterday and the prospect of two weeks of doing that was very daunting.
Now if only they really were buffing mounts and it extended to the Love Rocket