Sounds like an hour to see someone else and an hour to clean up and wait for you to arrive.
Pushing things back say, 30-45 minutes, I would be less inclined to think this. Maybe she does have legit other reasons. Who knows. It seems too coincidental to me that she would need should an exact particular amount of time, one that allows for such a large window, where anything else (i.e. another visit) to happen.
Could just be my paranoia doing the thinking here. When I was strong into BP, I used to go with a 20-minute rule (I'll be there in 20), making it hard(er) to squeeze in anyone else before me.