Benefits end date after a layoff - 4 weeks in

I was told my coverage ends on my last day, but the letter says the end of the month. There are 9 people counting on me, so I am trying to be careful. The letter is unclear about dental and vision. Did coverage match what HR said?

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.