Just confirmed from Squirrel, the 20-40 pins per week is definitely a mix of JCH and UKR. So if we assume the ratio previously mentioned of 2 : 1 on the floor you should be able to roughly guesstimate your build week at 10/wk for UKR. (YMMV)
For example if your #100 your build will be ten weeks out so expect to see an email from Spooky about 7 weeks from now.
This only counts for CE AFAIK, because they will likely need to switch the lines to entirely JCH CE until they get built out, then back to a 2 : 1 build for the BSEs, and repeat for SEs.