Sleeping Sherlock doesn't happen as often now. It does happen less now that John is also residing at 221B Baker Street, but not much less.
By less, I mean, yes, Sherlock did sleep, and technically he did get 6 hours a night, 42 hours a week before John moved in, it's just that the 42 hours did not actually equate to 6 hours a night. It could have equated to 12 hours each day for 2 days, and then cat naps and longer naps over another 3 days, with an awake period of 36-48 hours, depending of course on the case, and whether there was a case at all. It could also have equated to any other mix of hours.
Sherlock's sleep is more, well, normal is not the right word, for what is normal, but scheduled, if you wish, since John moved in. Regular food and fluid intake have played a part, helped his body to set a rhythm that has Sherlock cursing John loudly at 3:30 every afternoon if lunch was consumed between 11 and 1, and praising John silently when a cup of tea is pressed into his hands in the morning.
So as you can see, Sherlock is falling asleep less often, but sleeping for longer, hence my statement that Sherlock sleeping doesn't happen as often now.
John is just glad there's not as much playing of loud music on the violin at 3 in the morning.