Blue Cumulus vouchers can still also be redeemed in paper form. A Cumulus voucher can only be redeemed once. This means that if a voucher has been redeemed digitally (via the app), it can no longer be redeemed physically. (Notification will appear at checkout). Physically redeemed Cumulus vouchers are listed under your redeemed vouchers on the website and the app and can no longer be redeemed (digitally).