Now that you mention it. My miners went off line this morning during the change. I'll have to remember to note it if it happens again. Since who knows if that is a trend or not. But I think I recall they went off line during the last change also.
Also who knows if there has been any ddoss on any mining pools before this change happens that could be a reason also.
Or even some company just happens to be testing there devices for a few days to burn them in before shipping.
It's an intresting thought.