The Red Line is just not running between Park Street and Kendall. They have buses lined up (it's quite a sight) outside of Park to take peope (for free, go MBTA, what was that about a fare increase again?) to the stops. I have no idea for how long, but I can tell you that the first I learned of this was when the train was pulling into Downtown Crossing.
Presumably they are also letting people back on the train once we get to Kendall for free. WTF.