I think I'd use every form of communication going (so fb, text, email for now) telling them that any missed weeks MUST be paid for as you still have rent/activities to pay for and that subs MUST be brought up to date next week for those who owe as you have paid for their activities regardless of whether they pay or not(unless exceptional circs). Then next week a note home saying any missed weeks MUST BE PAID FOR and subs must be kept up to date for you to be able to continue to provide a variety of activities for the Rainbows.
Having said that about exceptional circs, the Rainbow whose mum lost the baby has still paid up to date (well, last week as she didn't come this week). The message I got told me that nana had subs up to then as she was expecting to pay even though the Rainbow hasn't returned yet.
I'm in a bit of a pickle about that one - I can't hold the place forever & know the Rainbow has been sent home from school several times the past few weeks as one of her classmates is in our unit, but it's been 5 weeks & she shows no sign of returning to us and I have a waiting list. I'm just not sure whether to let her be and see after half term (we're having two weeks off from 17th) so that'll have been near on 3 months she hasn't come to a meeting. TELL ME WHAT TO DOOOOOOOOOO!