After lots of people freaking out about it, we finally have it, woo!
A good quality image of the theatrical poster for Digimon Adventure tri. Part 5 Symbiosis!
The poster image has also added text to show that it's scheduled for a theatrical release in 2017 (which we knew, but nice to have it on the poster image to reconfirm.)
Previous thread with prior information and discussion is here.
At least at the time of this posting, the overall tri. website is still themed after Digimon Adventure tri. Part 4.
Update- An even better version via Toei USA.
Significantly larger, just without the 2017 date, with some English credits added.
Thanks to neko for the heads up.