Improve logic checks when copying orders

Scenario for you.

A while ago we moved from using Carrier A to generate our Royal Mail labels to use Carrier B.

The old services against Carrier A were renamed and set to inactive.

We've seen it recently where a client has copied an old order where the courier was set to one of these inactive services and the order has kept this courier method. Surely it should have gone to 'no courier allocated' as there was not an active courier service........?

We monitor orders in various ways to create batches but in both scenarios, orders like this would be missed. Carrier A isn't an active courier so we've not looking for orders (first fail) and secondly we monitor by service name and as this have been renamed, we miss the order(s) this way.

Luckily this is (effectively) Royal Mail to Royal Mail so we got away with it but what if the original order was UPS and a 3PL no longer uses them? Slightly more complicated!