Yes, generally, cars for the northeast and midwest are shipped to Chicago (Goose Island if I remember correctly). Cars for southeast are shipped to Riviera Beach in Florida. Cars for south central US are shipped to Houston. West coast has a potpourri of options. I think Goose Island and Riviera Beach are both Service Centers, so I am not sure how you reconcile that. My understanding was that the PDI (Pre-Delivery Inspections) are done at Service Centers. Makes sense if they find anything.
What has changed in the past few weeks is the number and magnitude of the inspections. It does appear that something happened, or did not happen in Casa Grande to cause this, but it is really just speculation for the most part as Lucid has not been too open with details. There has been a bit of talk about panel gap issues. What took a certain amount of time prior to the end of April now takes much longer and they are having to go through the process on quite a number of cars. So, I see this as a three-pronged issue; getting the cars in the Service Centers inspected fixed and delivered; inspecting and fixing the cars at Casa Grande that were produced before the changes so they can go to the Service Center; and resuming whatever the new normal is.