It'll be interesting to see how the club handles his progress...By the time he's completed his 3rd season with Barça B, he'll still be 19 years old...Alba will only be 26 so shouldn't be a big problem rotating him with Jordi once he does progress.
Now that's assuming he isn't banging on the first team door when he's 18, after just two seasons with the B team - which is entirely conceivable
It's his contract that will be the biggest issue ultimately which will have to be sorted in the coming year but I imagine the club has very high hopes for the player...He's not on Alba's level, far from it still but I do love the way he plays and the intensity in which he does it...He's a competitor and leader on the pitch
B team experience will go a long way in preparing him for first team football and defending, even under a joke of a manager in Eusebio