Train Waggons

Like the possibility option to simply add or remove Train Wagons. Just produce or reduce an additional Wagon and not replace the whole Train.

What, like, if you edit a train, it'll try to head back to the depot to get itself "rebuilt"?
(but not actually dismantling any trains or wagons unless they were removed from the design)
Keep in mind that the train depot + extensions are intended as part of the train's logistical challenge, so they should not be ignored or otherwise circumvented.