Help to decode Brompton-Bremont-Cheaney P-Line SKU?

Hi all!

First original post in reddit, and soon to be first time Brompton owner/rider once my ordered Brompton-Bremont-Cheaney P-Line 12 speed arrives.

I have found out that the stock-keeping unit (SKU) for this model is as follows:

M12L/mBGg/rTi/FCB/BAT3/SP/50T/BRKM/TYCB

I am trying to decode what this all means, and would like to ask for your help, although I am not fully sure this SKU is the Brompton HQ 'official' SKU.

M13L obviously means: M handle, 12 speed, L=mudguards/no rear rack.

But the followings are difficult to decode.

mBGg: could be of the color? m=main fame?, BG=Brunswick Green?, g=???

rTi: rear frame or raw titanium?

FCB: Front Carrier Block (Edit 4 min later)

BAT3: ???

SP:

50T: Front gearing teeth number?

BRKM: ???

TYCB: ???

I guess I should search for other Brompton models' SKU for hints.

Anyone with a good guess or deep knowledge?

Thanks in advance!