I posted something on this topic a week or so ago, but didn't get any response. I'm hypothyroid, and have recently changed from Levoxyl to Synthroid due to a drug recall, and I've been losing steadily since the day I switched!
I had been on a plateau since about November, which I found puzzling, since I was sticking to plan, but I tried to just "hang in there." When the scale started moving, I really didn't know what could be causing it, but I thought back to the change in my medication, which was the only thing different.
I'm not sure if the effect will last, but so far, so good. My goal is around the same as yours, so if this helps me get that far, then I'm all for it! Hope your experience is positive, too!
Losing again since January 2012
"Tomorrow is a new day; You shall begin it well and serenely and with too high a spirit to be cumbered with your old nonsense." Ralph Waldo Emerson
(3.10.14) I resolve to lose the last 60lbs to make it all the way to goal! One blossom = 5lbs