Lisa AF, did you mean Adventureland? Frontierland has, to the best of my knowledge, always opened at 9 am (except for Country Bears, which almost always opens at 10).
I thought Frontierland was the part that opened later. I've always avoided it in the past thinking it wasn't open. The problem probably is that I hadn't found the Disboards to keep me completely informed! I am now, can't wait to leave. 3 more days!!!