I mean... I could have asked, and they might have been able to transfer, but there's no user accessible way to make it happen, and you can't (or couldn't) make a new order while one was pending. But I was coming back from kid's hockey practice and tired and now mad at mcdonalds, so I wasn't going to wait in line to ask. I have ordered to the wrong Starbucks, where they do start your order when you place it, and they were able to see the order and remake it at the one I actually showed up at, but Starbucks is always super nice whenever anything goes wrong, even if when it's my fault, which it usually is.

Not being able to start a new order is also great when you had a successful order that the app didn't notice and then you have to clear app data days later when you want to order again... but I think McDonalds may have added a button to just order anyway in the past not too long.