When does my employer coverage actually end? - 15 weeks in

I am not sure what date my benefits stop after being let go as a medical assistant. There are 14 people counting on me, so I am trying to be careful. The letter is unclear about dental and vision. How did you confirm your end date?

I moved my appointments earlier while coverage was active. It saved me a bill.

Dental and vision sometimes end on a different date from medical. Mine did.