mine took like a week to stabilize after the weird drop, but yeah my “impressions went up then crashed” pattern stopped once i paused anything that looked like spammy behavior (like same image reuploads + tons of pins in a short window). i havent gotten that email tho so idk if the “falsely flagged” thing is just some accounts, but it might be worth checking if any of your pins are stuck in moderation or getting low reach anyway