Pasadena has a large stock of genuinely historic houses and a lot of them are on raised foundations with original plaster, wood floors and period detailing that is worth preserving.
That changes the priority. On a house like that the job is to dry the materials rather than remove them, which takes longer and needs monitoring rather than a fixed schedule.
What goes wrong in Pasadena homes
Old supply pipe inside deep wall cavities, cast iron drains at the end of their life, and under-floor leaks in the crawl space are the recurring sources.
The Arroyo side adds storm drainage. Properties near the canyon edges take runoff that arrives quickly during an atmospheric river, and where it collects is decided by grade rather than by anything anybody built.
Will drying damage my original plaster?
Done properly, no. Plaster tolerates drying better than it tolerates being left wet. What damages it is aggressive heat or being removed unnecessarily by somebody treating it as drywall.
How long does drying an old house take?
Longer than a modern one, because the materials are denser and hold more. Expect monitoring over several days rather than a fixed number, and ask for the daily moisture readings.