Among the collections found in the Miscellaneous Drawers in the San Mateo County Record Center is a list of "Cancelled Architects". These are architects who had been licensed to practice in the county in the past, but whose authorization was now revoked. Sometimes the reason is noted with the most frequent note indicating non-payment, but more than a few state death, and a couple state by request. Quite a few give no reason.
The dates cover the time period "before 1904" to 1932.
The list might give a glimmer into the retirement or death of a local architect, or give an approximate time table for movement to another place.
Further information on the architects on this list might be found on the Pacific Coast Architecture Database - Information on buildings and architects in California, Oregon and Washington maintained by the University of Washington.
Brothers, Ernest and Almario Coxhead (Coxhead and Coxhead, a partnership) were cancelled in 1908. Both have page long biographies which include links to the buildings they designed.