I flew yesterday from Hayden (Steamboat Colorado) to Dallas Ft. Worth and the gate agent announced she was going to do things differently and board the plane from the back to the front because there was only 1 set of stairs today. She proceeded to board first class, exec platinum, and platinum. Then boarded groups 2 through 6 and lastly, group 1. Since I am an AAdvantage Gold, I boarded last.

Has this happened to anyone else? What are the exact rules for us lowly Gold status passangers on boarding the aircraft?

I don't see how this situation is any different than other boardings as;
1. one set of stairs is no different than one jet bridge; and
2. except for passangers needing assistance, first class, exec platinum, platinum, and group 1, planes load from back to front based on the group order anyway.