There is no issue, although on a 9651 the only relevant bus checks it's doing are for keypads. A longish wait is normal, I upgraded a 9853 last week with a second keypad and xpander and that takes about the same time to get to 'exit engineer?'. Other than mains or battery, if there are faults it can see, it won't let you exit.
The only specific bellbox fault this panel can detect is an open tamper.