This... but only up to where the bar is a 'buffer' of exp, to where it goes one exp short of level 51. It shouldn't go beyond that. It never does in MMOs. Or else what would be the point of raising the level cap, if all the people playing would just fly several levels from all the grinding they did? They need a 'gate' there somewhat to prevent this. Not receiving exp is that gate. If they didn't, then you'd just have people complaining about 'nothing to do' more than you see some do now, due to them not having to level when the cap is raised.