I had a situation come up today that I had never encountered before. I was a little ways into a house cleaning when I got a phone call asking / telling me that I had to report in for my regular job ASAP. I felt bad having to tell the homeowner, but I had told them, just as I tell each of my clients, that I work for the local Town and could be called in at any minute. The homeowner was very understanding. 5 hours later I make it back out to the house to finish up and the homeowner is trying to make me lunch! While I was away they had the chance to walk around and see what had been done and they were impressed. Finished the job, was tipped generously, and was asked to stop by the neighbor’s house to provide a quote. For a situation that I felt was truly unprofessional it sure turned out well!
It always works out. Even when it doesn’t.
I don’t think you where unprofessional, you notified them before hand that you might have to leave at any given moment… I think its respectable! 
I can see it being ok with some customers but not all of them, I guess it’s a tiny bit unprofessional but I’m biased because I’m a business owner and not a consumer of my own services. If a plumber came to my house to do some repairs and we had a schedule I would expect them to not have something more important to do other than my scheduled leaking tap that’s important to me, that’s where my disappointment would come from. I think you get the gist of what I’m saying.
So your saying…
Lol oh let’s not go there the last time you went there ole racer gave you clip around the ear 
Hell , If I counted the times I’ve been clipped I’d be a wealthy man by now. You more than others know that rubbin is racing.
The only time I’ve had feedback from customers on rescheduling is when they specifically took time off from work to get their windows done.
