All have the “1791” on the dial. All the others have the single bridge.
The only answer I could get was that GP is still clearing old stock.
I don’t understand that because it has been about 17 months since the single bridge came out for the copper dial.
I think maybe they are going to discontinue the 42 mm and don’t want to hassle with the change in the machining and such. Or they really have cupboard and cupboard if blue dial and such already printed out.
The dials are stamped. The size of the stamps for the “1791” is smaller than that of the single bridge. Don’t think they want to waste what has been already stamped.
Green dial is with the single bridge. The rehaut color is different from the blue etc.