I hadn't heard of this, so googled it as it sounded interesting to us as well, but I can't find anything to say it's running this year. All the information is dated 2016. Have you seen it advertised for Christmas 2017?
Wonderful, thanks, we'll check that out (and following this thread to see who's been and what they think)There is a section towards the bottom of the TRex page with details.
https://disneyworld.disney.go.com/dining/disney-springs/t-rex/