I work differently to most of you guys. I have my regulars, with differing frequencies according to their requirements, as well as others who phone me as and when they need me.
At the moment I am snowed under with work, so if I get a regular who asks me to leave them this time, it's doing me a favour by helping me to get round to everyone who wants me this month.
I don't drop any who are 'not todays' unless they do it 3 times in a row, in which case I move them to the 'call me as and when needed' category. If I make some bucks from them during the year, even if it's only occasionally, I'd rather keep them than cut off any chance to earn from them.
John