I had an instance fail (unresponsive then with that same stop/start delay) on the same day in two consecutive years. I remember because it happened to be Valentine's Day, and I had to break out the laptop for while to check on things. I always wondered if that was a completely random occurrence, or part of some maintenance schedule that randomly affected me twice.

The last place I worked has a policy of making zero changes in production Friday-Sunday or around holidays. It was one of their better practices.