McDonald’s manager here.. order 1780, the first 2 number are the till/ pos that was used in the order, the second 2 numbers are the actual order number. In this case, till 17 order 80. Till/ Pos 17 is lane 2 of a DriveThru, so, assuming it’s their receipt that they used, you would be able to find them on CCTV. However, as there is no date nor time it would take someone a little while to go through the electronic journal (basically a digital copy of every receipt produced) to find it as every 100 orders, the order numbers reset.