[IBR-156-OM] - Import date (BTOM-020) MUST be formatted in YYYY-MM-DD.
IBR-156-OMubl:Invoice | cn:CreditNotenot(cac:Delivery/cac:Shipment/cac:Delivery/cbc:ActualDeliveryDate) or matches(cac:Delivery/cac:Shipment/cac:Delivery/cbc:ActualDeliveryDate,'^\d{4}-\d{2}-\d{2}$')