I can only go from what DS was like but he would cluster feed in the evenings as well, i think he stopped at about 2 months old and my supply at night has always been awesome now. Like the other ladies have suggested he is probably going through a wonder week, growth spurt all which will help build up your supply

If you think its lacking at night right now have you tryed the lactation cookies? I make up a batch whenever i feel my supply is a little low (generally around the time AF visits) and it boosts straight back up and then some, not so much how much is there but the milk is alot richer and creamier.

HTH