Unless payment is deferred, delayed, or set-off under COMAR 21.02.07.03, payment under a procurement contract shall be made within 30 days: After the day on which the payment becomes due under the procurement contract; or If later, after the day on which the agency receives a proper invoice. Payment will be considered to be made on the settlement date for an electronic funds transfer payment or the mailing date of the check for a check payment. Payments falling due on a weekend, State holiday, or federal holiday may be made on the following business day without incurring late payment interest penalties.