Not done this before and I think I have managed to say no to substitutes but can anybody tell me whether they tell you online if they have substituted something before the shop leaves their store.
I don't want to have to deal with the person doing the delivery if I can avoid it. I would just like them to be able to leave the stuff at my front door and to thank them and they go away.
It looks like if they do substitute something you have to give it back to them and I don't know how to do that without having to interact with them if you see what I mean.