The setup on the old Soul’s was more suited to a 100 – 120mm fork. I bought a second hand earlier this year and spoke with Cotic about it before putting forks onto it. (perhaps I used the wrong terminology saying the geometry was different)
As for the Soda, you could run it with 130 – 140mm I guess but I think the handling would be pretty poor, also Cy recommends 100 – 120mm with the Soda.
For me the bolt through Fox F120 (or Reba/SID equivalent) with a nice wheelset is perfect on the Soda.
Going back to the OP, I am sure you will love it with 100 or 120mm forks, its a brilliant frame to build around.