University admissions scanning personal statements for AI now

I mentor a handful of grade 12 students applying to competitive programs every year and just found out through a colleague that at least two Ontario universities are now running submitted personal statements through AI detection before the file even reaches an admissions reader. Nobody tells the applicant this is happening, it just quietly flags the file for extra scrutiny. My students already stress endlessly over these essays, most of them use some kind of tool along the way even if its just a grammar checker for polish, and now I’m wondering what advice to actually give them. Do I tell them to avoid any AI tool entirely just to be safe, even something as basic as a grammar checker? Or is that overkill given detectors mostly target generative tools not grammar correction. Trying to figure out what’s actually reasonable to tell a nervous 17 year old without either scaring them unnecessarily or leaving them exposed to a flag they didnt see coming.