If that's her attitude, I think I would be booking another appointment and then calling her a couple of minutes before start time to say that you've decided to "extend your time in the pub by one hour" - bet she wouldn't appreciate that but "do as thy would be done by" as it says in the Good Book! Better luck next time, mate.
Haha...what gets me is that she felt totally at ease with her explanation as if wasting my time due to another client wanting to stay longer is entirely blameless. I missed one small detail that maybe should have stopped me from going which is that I had to call her twice to receive the post code. The first post code she gave me was bogus although she could have genuinely made a mistake or just given me the wrong one to buy herself more time.
At least she she saved me from sinning yet again.
The lord works in mysterious ways.