Use this event to
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[EventSubscriber(ObjectType::Codeunit, Codeunit::"MOB WMS Pack Adhoc Reg-PostPck", 'OnPostAdhocRegistrationOnPostPacking_OnBeforeRunWhsePostShipment', '', false, false)]
localprocedure OnPostAdhocRegistrationOnPostPacking_OnBeforeRunWhsePostShipment(var _WhseShipmentLine: Record"Warehouse Shipment Line"; var _WhsePostShipment: Codeunit"Whse.-Post Shipment"; var _IsHandled: Boolean);
begin
end;
...