Whenever you submit a run, the run is pretty much counted in the same manner as a verified run. It increases your run count, the number of games you played, increases the run count in the game stats. And so once it's verified nothing else about it actually changes. If the run is rejected though, it's immediately pulled from whatever table allows it to be calculated into stats.

So, I guess not too surprising it would also show up as having a PB on the streams page before the run is actually verified.

That's interesting. I suppose then the run stays counted until the rejected run is actually deleted by the player who submitted it?