Has it been released yet? I'm not seeing GPT 5.6 anywhere in the selectors, nor any announcement about it, but you're talking about it as it's already been released?

There's something like 20 companies with access.

Isn't it like 99% sure all those companies got that access to it together with NDAs and other goodies?

Some of them will publicly break it for whatever reason, an NVIDIA engineer (@blelbach) recently made some posts on X about his results using 5.6 Sol Ultra to optimize stuff and then deleted them shortly after (presumably got yelled at).