You've received good advice above. One thing I'll add - the reason this is happening this year and might not have happened before might not be directly related to the grade skip, but instead might be related to a change in school and a different school culture surrounding how students' social-emotional needs are met and handled. Part of that might be due simply to it being middle school vs elementary where children are all with the same teacher all day vs changing classes and teachers seeing lots of students for short periods of time - or it might be due to attitude of the administration and emphasis (or lack of it) of inclusiveness etc.
In this situation, I would probably actually try to talk to the school staff first, rather than starting with an email - but if an email is what's needed to schedule a meeting to talk, then definitely email! You need to know what the situation looks like from the teachers' perspective, and you need to talk in person in order to get a better understanding of how the school handles this type of issue.
Best wishes,
polarbear
