I work for a catering company. One thing we always ask clients is to send us a finalized order so that we can get the food ect. at least three days in advance and prepare it accordingly. The thing that irks me about a job I did last night, as we were preparing the main dish the client asks if he can change what the dish is. Uhm...no. Sorry, but I'm making it now, you should have said something sooner.