When does my employer coverage actually end? - any advice?

HR said my health plan continues for a bit and I do not understand how. There are 6 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.

Keep a copy of any coverage confirmation in case of later disputes.