If something comes up, and you don’t think you’re going to be in the most convenient location to have an interview, I think it’s OK to ask to reschedule (in advance).
You probably only have 1 shot at presenting your best self.
Employers do it all the time, you should have the ability to do so as well.
If they’re genuinely interested, they should understand.
I suggest only once though…
You may even want to tell them why, if you’re comfortable doing so.