I just ran through a quick test and found out that 5 of my accounts stopped following at one point of time during the day. Follow tool is active, but it does not follow. It says: "next run: 3:20.21" and that time passed. After I pressed stop/start auto follow, some started following again, some did not.
So, I am taking a wild guess here: could it be that once an account for some reason does not find anyone to follow in one of the follow sources, it freezes auto follow function for that day, and restarts after MP update or night mode?
I noticed some accounts follow less then others, but they follow every day. I do not have a single account with zero follows per day. So, all of them start following, follow some people, stop for some reason and restart tomorrow. Why do they stop at one point, and do not restart by them selves the same day?