I believe you can ask for a substitute and normally get it. For the next question i would ask where my items are but i would check and make sure i was charged for it.
Being able to get sausage on your mcgriddle and not the next could be the fault of the crew person not knowing if it was allowed or not. If you don't get what you order don't be afraid to run back in and tell them but check your receipt...it might not have been ordered even though you thought you did.
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