A FWIW update...
I just got off the phone with James, whom I called with some other power section related Q’s; and the status of the 1200 W module is that a) he wasn’t happy with some performance aspects of the early module release, and is waiting for those to be resolved; and b) didn’t get much enthusiasm from this thread and other input to make the development an urgent priority. So, he is still looking at the higher wattage module, but biding his time waiting for certain improvements.
Meanwhile, (spoiler alert) he has pressed ahead with a compact preamp using the Bass400 chassis to be used in ampless / IEM setups. The unit has a bunch of pretty useful features designed for small footprint / big sound to the board. It of course will also drive a power amp on a cab for traditional preamp use. Sounds pretty interesting. Price is about $700, with first unit shipping about right now.