Obihai certainly know how to make one firmware work on different models.
Obi100 and Obi110 - same firmware
OBi200, OBi202, Obi300 and Obi 302 - same firmware
OBi1022, OBi1032 and Obi 1062 - same firmware
My hunch is that even if the OBi212 and the 2xx/3xx models do not now have a common firmware, sooner or later they will.