JMHO - I found it very helpful to state my leave time in my service agreement. i.e. **** Medical Billing Co. will be closed from Dec 15th until Dec 31st for vacation. I send out an email a week before vacation stating all claims must be received before noon on Dec 14th to be processed and submitted before the 1st of the following year.
I'll stop working with providers if our personalities don't sync. I try for a few months to see if we'll get on the same page but if we don't, I tell them that we are just not a good fit and they will be happier in the long run with someone else.