happens. sometimes they just seem to hit a snag and don't draw stuff out. look well to make sure there is nothing bad going on. remember that they will draw what they need, so if they are not building up, make sure there is nothing holding them back. if your 1st box is getting jammed and they still won't move, you can take some frames of brood and move them into the new box. otherwise, don't worry to much about it now if everything looks good. you can reduce size before winter and save those drawn frames for next year.