Yes, the expiry of coupons can be extended and this applies to both pre generated and dynamically generated coupons. This can be done for coupons that have not reached expiry as well as coupons that have already expired.
NOTE: The ability to make these changes to the expiry is limited to Punchh internally. If an expiry update is needed please submit a support ticket. (For help submitting a ticket, click here)
If further assistance is required, submit a ticket to Punchh Support. (For help submitting a ticket, click here)