Target Release Date?

The part is in production and released but only available under NDA.  ADBMS6830B is very similar and available without NDA. https://www.analog.com/en/products/adbms6830b.html

I have an active NDA regarding this part.  I had to get it to get the datasheet (which I niow have).  But when I asked about hardware, I was told to check with distributors.  W

Who do I talk to sample/buy chips?

Please reach out to your support FAE for details.

Surely by now, there's a better answer, or at least a "no sooner than" date.  Analog.com shows that the parts are now available for sale, but the production ones are only available for sale in quantities of 2,500 part reels, and only directly from ADI.  The 260 part count trays seem like they could be purchased, but again only from ADI.  The public datasheet is still heavily redacted and no distributors have stock.  
The ADBMS6830B suggested above may be available, but it doesn't have the same bandwidth or anti-aliasing capabilities.  For planning purposes, it would be really nice to be able to pencil in a date when distributors might have stock, or failing that, at least a no-sooner-than date.

EZ is for technical discussions and since this is not really a technical question we cannot answer anything related to your question. Reach out to whoever you signed NDA with for getting more details about ADBMS6833.