If you are certain that is a ZF case, then it appears the BBR movement is inside it. Look carefully at the movement in the above picture and you can see it has moving balance wheel whereas pics of ZF do not show the gear just above 6 o'clock
Interesting points raised here but at this time I think there’s no use speculating. If the movement does indeed fit the ZF case with minimal changes, I’m confident we will see an updated ZF version with the same movement within a month or so, just like the situation we had with the APS 3120 clone.