Honestly, my bet was on a decrease in server quality/performance. Player numbers have gone significantly down over the last 4 years, and while I occasionally saw this prop up before, it has only become regular lately.
Seems to usually occur around 11:00 EST, or an hour or so before turn change. For me at least.
It is possible that since Tom has gone to a hosting service, that they are limiting the amount of concurrent connections in order to reduce the load on their system. It is hard to say without details of what kind of hosting he has.
