Was there any event last year?
Yes, as mentioned we got the Grymforge added content but it wasn't quite ready exactly on the date.
We got the additional area because Larian felt bad about EA taking so long (and people had access this area unfinished through a special editor).
So, I'm hoping we get something for completing Year 2! It feels right for such a company that loves putting on a spectacle with little substance.
Pretty sure that the studio will prefer to put as little emphasis as possible on the fact that they clocked 2 full years of EA without a release.
Not to mention that they will most likely be busy as hell working on the final stretch of the game.
2 full years and not all classes patched in, many game mechanics broken, and likely to go over 3 years before the game is playable.
I hope we get something more than just a tweet.