The Junghans J80/8 is the predecessor of the J80/12. The series was probably only produced for a few months.
Again, I find it difficult in some caliber allocation. With the above list I tried to provide some clarity on the different caliber and their designations.
The movements were produced at the same time with or without divided wheel bridge. There are versions with 7, 11, 13, 15, 16 and 17 jewels.
There's caliber Junghans J80 with various imprints on the bridge: J80S; J80M (was probably Meister).