The problem was that they were ALREADY registered as Independents, and changing party to GOP had to be done way back before October. NEW registrations could happen just a month early but CHANGES had to be done more than six months ahead. Kind of crazy, but it does prevent Dims from messing up primaries with operation chaos antics.
http://static.latimes.com/american-independent-party-california-voters/
The American Independent Party is California's largest third party.
Who knew Rio Linda encompassed such a large part of the Golden State?