I plan to remove the US 101 business route in Ukiah from the usausb system, in my next batch of California updates.
As noted in neroute2's extensive peer review of the preview usaca system, there is no Business US 101 signage either on the business route itself, or on Caltrans-maintained signage at exits from US 101, or at junctions with intersecting state routes (CA 253, unsigned CA 222). That was based on the latest 2019 GSMV imagery, and also in the
AARoads California guide. It also was that way on my last visit to Ukiah in 2017, though I didn't then do a thorough look for business route signage. So it seems to have been unsigned for awhile, and can be safely deleted.
There's been some concern about over-haste in removing California business routes, when I noted apparently weak or nonexistent signage on some of I-5 business loops. Since then, I've taken a closer look at all of California's Interstate and U.S. business routes in the HB. All of them, except the one in Ukiah, have at least some business route signage, especially at freeway exits.