For anyone else looking, found this discussion, which is at least more involved and has some citations.
TL;DR; There is no consensus... but two basic camps
1. CSG has said turnaround time start when a package is delivered to their facility. This would make the most sense and is listed on the site in several places.
2. That's impossible, because it's not what's happening, so it must start when orders are entered into their system. Turnaround times seem to match if the date an order is entered into the system is used as a start. This still doesn't explain what "Now Opening" means, but is based on real world observations by customers.
Wish someone would step in and at least clarify the terms here. I really hope CSG makes it, but there's not a lot of things worse for a business than knowingly misleading your customers. You've got more work than you can handle, that's a great problem to have, that whole marketing machine doesn't need to bring in more business right now. Use it instead to build good will, understand the current status, build a long lasting community, and just give realistic expectations. Please.
Sorry, looks like I posted this in the wrong forum. If there's a cleanup crew, please feel free to move it.