Benefits end date after a layoff after 17 years as an electrician's helper

I am not sure what date my benefits stop after being let go as an electrician's helper. I worked as an electrician's helper before this. The letter is unclear about dental and vision. 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.