@jon we're getting back to Berlin from Italy right now. Took RJ 84, it departed Bologna with +76 for some reason. From Bologna to Brenner it gained some and lost some, arriving to Brenner with the same +76.
Halfway between Brenner and Innsbruck, DB started displaying that it's going to be cancelled after Rosenheim, while train displays (and ÖBB) still displayed projected arrival to Munchen with like +60.
Asked train manager what's going on, but he didn't know and thought we're going to reach Munchen, said that he will have more information by Jenbach or Wörgl.
Asked him again in Jenbach, and maybe I misunderstood him but I think that he said that German border controls won't let the train in beyond Rosenheim, because it's so delayed and there is RJ 82 after it.
So eventually we arrived to Rosenheim with +122, train unloaded all passengers there, and we all had to walk to another platform to board RJ 82 with +20 (breaking all connections passengers on RJ 84 might have had of course).
A bunch of police loaded at Innsbruck IIRC, they were a menacing presence on the train as the delay increased from +76 to +122. I'm not sure if they were Austrian or German though; I saw them doing some document checks but didn't see who they were checking, and not sure what happened later.