And going from what Daisy said, you want to put this ball in their court, but maybe do it with the "I'm confused, could you please clarify this for me" route....
Don't get into a spitting mach about the classroom hours. If he wants to go that route, ask him to tell you how many hours are spent preparing and taking mandatory state tests. If they took out some of those hours, then this wouldn't be falling into your lap.
I am assuming you have a 504.
Something along the lines of....
Dear Mr. So and So:
I'm writing about your phone call to me on ____ date when you stated that my son's classroom accommodations are going to be removed from his 504 plan for next year. If I understand correctly _________ (state what you understood here)
I'm confused as to how a 504 accommodation can be removed from a 504 plan when a child's disability has not changed? Could you please clarify this aspect of the 504 process for me as I do not see anything listed about this on the 504 section of the district website? I did not realize that specific 504 accommodations could be removed when a school decides they should be, rather than being based upon whether or not the student's medical condition has changed. My child's disability has not changed since his 504 was granted. These accommodations are still necessary and appropriate for his age and disability. Compromising those accommodations puts my child in a situation where he will not be focused on learning in the classroom- he will spend his time focused on the food around him. My child has plenty of places where he must practice navigating food in society. As you know, the classroom is a place for learning. Negotiating food and managing the stress that goes along with food is not conducive to an an equal learning environment to that of his peers. I expect that my child will continue to have his accomodations in the second grade classroom, as that is what FAPE requires. (someone fix the last two sentences of that for me)
Then end with something about how you know how happy your child is there, and that you are sure that you all can put your minds together to come up with something that works for the school's educational demands while keeping his 504 and food free classrom intact.
(someone help here with my wordsmithing- you old timers know where I'm going with this.... It's about two things 1) removing accommodations when there isn't a substantive change in condition and 2) giving him equal access to an education that does NOT involve food and the stress/anxiety that this disability has wrt food situations- distraction for learning, blah blah blah)
Legally, he can't just remove accommodations from the 504.