The following is a CARB certification which is required for every vehicle and powertrain combination. As you can see, the RWD 430i Gran Coupe is certified with both the auto and manual. The 2018 certification also has it listed. The 440i GC is certified for the auto only.

https://www.arb.ca.gov/msprog/onroad/cert/pcldtmdv/2017/bmw_pc_a0080433r1_2d0_s3-30_pz.pdf

Why you no sell 430i GC manual BMW?