So this was passed recently. https://leginfo.legislature.ca.gov/f...01720180AB3112
Begins July 1, 2019
This bill would make it unlawful to sell to any customer any quantity of nonodorized butane. The bill would exempt from the prohibition certain consumer items such as lighters and small containers of nonodorized butane used to refill these items. The bill would authorize a civil penalty to be assessed for the violation of these provisions. The bill would authorize specified local and state officials to bring a civil action to enforce these provisions.
Anyone out their making unlicensed concentrates is going to have to switch up their blend and probably get a set-up that can handle propane blends.

Interesting exceptions:

(b) The limitations in subdivisions (a) shall not apply to any of the following transactions:(1) Butane sold to manufacturers, wholesalers, resellers, or retailers solely for the purpose of resale.
(2) Butane sold to a person for use in a lawful commercial enterprise, including, but not limited to, a volatile solvent extraction activity licensed under Division 10 (commencing with Section 26000) of the Business and Professions Code or a medical cannabis collective or cooperative described in subdivision (b) of Section 11362.775 of this code, operating in compliance with all applicable state licensing requirements and local regulations governing that type of business.
(3) The sale of pocket lighters, utility lighters, grill lighters, torch lighters, butane gas appliances, refill canisters, gas cartridges, or other products that contain or use nonodorized butane and contain less than 150 milliliters of butane.
(4) The sale of any product in which butane is used as an aerosol propellant.
Some are planning to test recovery methods that would allow them to distill out the odor, but I don't think they will do a sufficient job.