Yes, the Dominion of Dragons will only arrive next year:
Cool things that unfortunately won’t be getting shipped this year:
“Dominion of Dragons” (working title)
A lot of progress has been made on this feature since January, but like we’ve said then, this is an update of unprecedented scale for the game and we still have some work left to do. We can’t wait to show you what we’ve been cooking up — hang in there!
Base update
Over the course of exploring our options for this, we came to the conclusion that we wanted our next base update to be something a bit more ambitious and exciting than simply raising the Stronghold’s maximum level and adding a new Advanced Building. Due to this, the Base will most likely not receive an update this year. We’re sorry about this change of plans, but we’re pretty certain that you’ll like the feature we’ve been developing in its stead. Please look forward to it!
I am not sure about it.
We will see once it reaches Beta, but what someone have written earlier about how it works in another game it should not be an alliance based event.