I am not a member of the club, but there are a few reasons that come to mind as to why the East side is not open yet.
First is that the lakes and swamps are not frozen up yet. All connections to the East side is via Couch and the trail going down to Lagoon City goes on Simcoe for a short piece, so until the lakes are safe (really safe and not make believe safe) these trails cannot be opened.
Secondly, the majority of the terrain on the East side is rough Canadian Shield with rock outcrops and very challenging topography. It takes twice the amount of snow on the East side to open the trails as opposed to the Rail Lines and farm fields on the West. Some areas could be opened on the East, but who wants to go so far and then have to turn back. There are those that would continue on and then you are into liability issues when they get into trouble. The trail can only be opened when the worst part of the system allows it.
Manpower may be an issue as well. Not enough volunteers to open everything up at once, so you pick the easiest trails to open up first.
There may be others reasons that those in the no could point out, but form my experience, these would be three of the big ones. I am sure things will start to open up in the next few days. A little more help from Mother Nature in the form of more snow would't hurt, but this cold weather with not much snow might be a blessing in disguise. Get things frozen up first, then give us our snow.
Happy Sledding, Charles