Lipman announced on their website that there will be two phases of construction. First one for 8 rides, which will be finished for june. The second is the construction of Big Dipper, and will be finished for the end of december.
To add to my previous post, here is a video construction update by CoasterLife which shows nice bright-orange Gerstlauer track pieces on-site, and a general overview of the progress:-
A few of the other rides appear to be assembled or on-site also. No sign of the Z-Discovery yet, however. And as @richardcrete points out about Big Dipper opening last, I don't imagine we will see any Hot Racer track on-site anytime soon.