My sister in law has one that blooms near constantly. In fact that inspired me to buy one this spring, but mine isn't blooming yet. We are in zone 8b SC.

I am finding that the conditions a Salvia has experienced 6, even 9, months previously has a big effect on bloom time. There are at least these three factors involved;

1. The length of time the plant was cut back, and how mature it is to begin with.

2. The time of year it was cut back.

3. The temperature conditions following its haircut.

Long-day (summer) blooming sages don't seem to be affected as much as short-day (winter, late autumn) bloomers.

The out of season blooming can be cut short by heat spells.

I would expect that prolonged optimal blooming temps out of season along the Pacific Coast to cause a lot of variance with short day plants. I don't see a lot of this where arid environments predominate. Here in North Carolina, this effect is unpredictable and needs to be studied.