Grey or black buttons

I have an ER-101 nostalgia flavor which has grey focus-buttons. I often come accros pictures of people with either an ER-101 or ER-102 (also nostalgia flavor) with black focus-buttons. Does this difference indicate a certain build period and/or version?
If I buy an ER-102 via the O|D shop, does it come with grey or black focus-buttons?

New ER-102 come with grey focus buttons. I don’t do black buttons anymore.