When does my employer coverage actually end? - what worked for you?

I am not sure what date my benefits stop after being let go as an HR coordinator. I have read a lot of threads here and could not find my exact situation. 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.

Keep everything in writing and save the confirmation numbers. It made the follow-up calls so much easier.