I'd take a close look at your rebills before you blame ccbill.

We were getting an unusual number of members that didn't rebill, and when we looked closely at the stats, it turned out that almost all of them were Visa Debit cards that were being returned as NSF (in other words, there was no money in the account when CCBill attempted to rebill)

A lot of our customers, at least, seem to run pretty close to the wire. They will place DVD orders and ask us to wait until payday to process the transaction, then call us to make sure that it went through OK.

So while CCBill may be somewhat conservative in scrubbing, you may also find that it's your own traffic and not ccbill...