Reg E says provisional credit has to be given within 10 business days of receiving the dispute if we cannot complete our investigation and received in writing, if we require it, which we do.

I have a case where the dispute came in on 6/3 and the provisional credit letter went out on 6/3. However, the customer's account wasn't actually credited with the provisional credit funds until 6/9. Since this is still within the 10 business days from dispute, I don't think I have a violation of the reg. Is this how others see it?

As long as the delay in deposit of the provisional credit did not cause an overdraft, I think no harm - no foul, but look at the cause of the delay and try to plug the gap.