The coordinators cannot tell a licensed user to drop power, move, or anything else except go narrow band. When a license is first issued that's when they get the power out rating based upon area of coverage that was requested on the license application. If you asked for 50 mi then you are going to get the max allowed, they aren't going to drop your power to 10 watts just because you ask for narrow band, but if you move your station then the coordinators can say you don't need full power for a 10 mi radius operation.
BTW you don't even have to deal with coordinators to go narrow band, just file with the FCC directly.