Yes. The amount paid by Gift Card will be reissued in the form of a voucher code and the remaining paid amount refunded as per the original method (by credit card or PayPal).
E.g. You purchased an item priced at $65 using a $50 Gift Card and paid the remaining $15 using your credit card. You decided to return the item for a refund. The refund you will receive is $50 reissued as a voucher code and $15 refunded back onto your credit card.
Note: you may see an incorrect value appear as you initiate the return online but we will process is accordingly once the return is received.