If you perform at an excellent level, in either Street or the League. The XP you get doesn't progress you to the next level. For example, I am on level 37, the progress bar is all the way toward the end of the level, played a game and got a 100 team grade, had an awesome stat line. End of the game, the progress meter literally didn't have any more room to go. And it's like I didn't even get the progress. This has happened three times in a row.