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 accounts payable clerk. This is my first time dealing with any of this. I have an appointment next week. What should I do about appointments?

Ask HR to confirm the exact date in writing. I also called the insurance company to double-check.

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