1.2 is absolutely not final, and I would not recommend making any.
1.26 is the final 1.2x branch - a finessed version of 1.2 with M2.5 holes and much better panel layout. It is not available publicly yet.
However, disclosure: I am working on 1.3 which uses a multiplexer to significantly reduce the number of pins required on a Teensy. It means we’ll just the outside two rows of pins, rather than the horrid SMD pads underneath the Teensy. One extra chip makes building the whole thing significantly easier and more reliable.
The reason there’s no release yet is that if it turns out 1.3 is a much better idea, it’d require firmware that differs in key ways to 1.26, and I don’t want to bifurcate the product: I’d rather people weren’t going “oh, which version should I use?”. I’d like everything to be backwards-compatible going out. So: let’s see if 1.3 is the line for final release. I should have 1.3 complete on my workbench this week.
I appreciate you would all like this yesterday. We apologise for the slight delay. We are only human.