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 a call-centre agent. The letter is unclear about dental and vision. What should I do about appointments?

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

Thanks for writing this out. I went through something close to it 10 months ago, and it got easier once I kept a simple log of every call and form.