I recently revisited CA 4 on a trip over Ebbetts Pass. That being the case I decided to take a deeper look into both variants of CA 207. The first CA 207 was aligned over what was Legislative Route 121 from CA 152 north to CA 33 Santa Nella. The first CA 207 existed from 1964 until it was consolidated into CA 33 circa 1972. The second CA 207 is far more interesting and lies in the Sierra Nevada Mountains near Bear Bear Valley and Lake Alpine. Present CA 207 traces it's origins back to Blood's Station of the 1860s Ebbetts Pass Toll Road. Private interests in the 1950s and 1960s led to the establishment of the Mount Reba Ski Area which opened in the winter of 1967. The Mount Reba Ski Area was sold in 1991 and is presently known as the Bear Valley Ski Area.
https://www.gribblenation.org/2018/06/california-state-route-207-i-ii.html