With respect to the new Reg Z requirements that go into effect on August 20, is it allowable to send periodic statements less than 21 days before the payment date if customers ask for that?

Not if your accounts are structured in a way that require the 21 day lead time. There is no provision in the regulation for waiving the requirement.

I thought you could send out less than 21 days, but if you do, you can't collect any late fees if they miss the due date?? Am I wrong?

GP - You are correct, but there a two more requirements in order not to abide by the 21 day deadline - dealing with grace periods and reporting to credit bureaus.