QuickBooks (QB) Payments doesn't have an exact time frame of when a requested refund for your customer will be clear. This will be based on the bank processing the refund.
As long as you requested 5 days passed since the initial transaction, it'll be refunded and cleared. For additional information, QB Payments allows refund processing within six months from the date of the sale. After this period, you can provide a refund using cash or check.