I get in a drill session once per week (1.5 hours). During the winter I'm playing a match roughly every other week, and during the summer probably once per week. Obviously wish I could play more. Tough to find the time.
Also, my shoulder just can't take serving more than once per week yet. Rehab seems to be helping, but it also seems to be two steps forward, one back. Every time I think I'm ready to step up the frequency, I re-injure it. Last match was 2 weeks ago and I'm just now able to go through my exercises pain-free.