Can only speak for HSL, and even then, my info is dated. Depending on where you go, and the time of year, it's about 10 months. Historically, HSL East always has aircraft, but their sims go down all the time. HSL West always has working sims (although they're getting worse) but the weather hinders flight ops in the spring/summer.
Obviously it's all cyclical. When I went through San Diego, we had maybe one working aircraft. Guys behind me were flying all the time, because they came out of the maintenance cycle.
I think the HSC (former HC) rag last about 3 weeks. They might even go to class once or twice. Of course I base this on the number of HAZREPS I see for HSC.
I keed, I keed.