California Code, Streets and Highways Code - SHC § 19234

Upon the withdrawal of any territory from the district, the remaining territory in the district shall continue as a lighting district until dissolved.  No withdrawal of territory shall become effective until any outstanding contract for service has expired or such contract has, with the consent of the person furnishing such service, been modified or canceled so as to relieve the district of further obligation to pay for future lighting service within the territory withdrawn.