I have always said yes. The law says, "Only one delinquency charge may be collected on any such loan installment regardless of the period during which it remains in default." So, if the April 1 payment was still past due in May, and you charged another fee for the April payment, you would be in violation. But you are now charging for May. One fee for each past due payment is ok, but not two fees for the same payment.
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I thought getting old would take longer.