Promotions stop after level 260 I believe. Chromium is the last LT you get from the promotions.
Would be nice if you guys could still continue it with the new LT every 10 levels and new promo every 20 levels.
P.S. balance this damn game out. People hitting me 700 levels higher is pretty annoying, I'm boycotting purchases until this gets fixed, otherwise this game is a waste.