You can create layered promotions by setting up a TPR and a Promotion for the same items. This will allow an item to have 2 discounts at the same time as well as 2 taxable rebates. Remember that a TPR is just a price change on the POS where S2k will send the old price back to the POS when it ends and a Promotion (without TPR checked) is a promotion that will be handled at the POS.