I think that a small anniversary update on the 3rd or 17th November is still possible. Some updates were released on thursdays, so maybe we could have it on the 5th, just the exact date of the anniversary. Then, the DLC could come on 15th December, just in time for Christmas. Of course, this is pure speculation, but this is what this thread is for, isn't it?
The anniversay update for Planet Coster was 1.4 and was launched on November, Then update 1.5 came in December. It matches the timeline (yeah, I know that doesn't guarantee anything, but there's a precedent for two big updates in less than a month).