I can't speak for the rest, but I can speak about the stuff I've been doing. Sculpting is the quickest part for me, but after that there's a ton of tedious stuff to do. Besides the feedback from Mark and other people on the team, I need to retopologize the meshes for animation, have it checked by animators, fix things, generate masks, generate textures in substance, import to UE4, and create the materials/shaders. In between every step I check with Mark for feedback. It's all pretty slow, and it doesn't lend itself well for a weekly update. That's why initially I jumped to other characters and quickly cobbled up some base sculpts for the Tsi-Hu and Kaiju. People like pics, so I gave them pics. Thing is, I knew I had to go back to finish the boring stuff eventually, and that's what I've been doing. I wish I could do things faster but my time is currently limited to a couple of hours after I get home from work. Also the holidays took a toll.
I think as far as weekly updates go, there will be times when there's no apparent progress and times with tons of stuff. Some things are starting to get finalized so there will probably be some nice updates soon.