We dose and 7am, 3pm, & 11pm.  On the nights when I’d like to get to bed early, I just get up for a few minutes at 11pm when to alarm goes of to give him his meds... he always sleeps through this dose anyway.  Sometimes I’d like more sleep, but like Corri, I’d rather be safe than sorry.  One thing I must admit though; sometimes I let him sleep until 8am before I give the AM dose, since he always wakes for that one.