Your question is Managing an Overpromised Client Commitment. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
A Producer has told a client that your team can deliver a service change or administrative exception, but after reviewing the request, you believe it will be very difficult or impossible to execute as promised. You need to protect the client relationship without creating internal friction or setting a precedent the service team cannot support.
How would you handle a situation where a Producer promises a client something that is administratively difficult or impossible to deliver?