Should I wait to put in an E5 packet until after I go to school for food specialist, or drop it before?

Here's the background, I had to go through a MMRB. Four years later I finally get the MAR2 results I am retainable but I have to reclass the only option immediately open to me is Food service. By the old scale I had 900+ promotion points, by the new scale I must have at least 600+ not sure exactly. Already have SSD1 completed, will get a slot for WLC after I finish MOS school in Feb./Mar. My chain of command says wait till I come back from school then they put me into the Mess Sgt. slot then go to WLC. I think they are afraid I either won't get it or will be forced to leave the unit to get it. What is everybodies thoughts?