Ann: Market Update - Progress Report, page-172

I dont recall them stating they would publish a spec sheet but could easily have missed it. That would certainly be an excellent news item. Somehow I still doubt we will see anything until the majors who have signed NDA's have completed their demos, testing, received answers to their questions and paid deposits on their orders. First mover advantage could be massive if this technology delivers the quality and range of sound expected.
We are all patiently waiting for some new information and yes a specs sheet would be a great start. Lets see what October 2021 delivers.