I think Bitcoin still has some upside left, but I don't think that it will be too high especially since it might soon be regulated (if govts somehow manage to pull it off).
Well it is not late in the sense that still bitcoin has too much potential and its price can increase too much, although bitcoin price has increased too much and people have already received a lot of money from it, but stil people are interested in bitcoin and they are still investing their money there. i am sure that if they will hold their bitcoin for some more time they will surely get a very good profit from it.