Yes, I have fired clients, well, only two, who were like this. As you noted, it isn't worth it to you or me to care more about their returns than they do. Recently I have been going on dive trips in the fall so have a much earlier deadline which has been honored. And I build in plenty of time for me to complete the work. About a month out I remind those stragglers that I will be out of the country so they should start looking around for someone else. This year, no stragglers!
Well, there are the new clients, one now in Berlin never having filed but we are almost caught up from 2011 and another new one who has to wait until Oct. 6 to meet the physical presence test. But her returns are actually finished.
Cranky is okay!