The timing lining up with a new friend group stands out to me, had a similar wake up call when the attendance office called about my son missing two mornings he swore were clerical mixups. Might have believed it if it hadn't started right after he began hanging with kids from a different grade we'd never met. Sat with the uncertainty for weeks before doing something. A neighbor mentioned uMobix cell phone tracker after dealing with nearly the same school call herself, said it helped confirm patterns instead of relying on "trust me" explanations. Caught an actual skipped morning within the first week.