I had the same problem with ordering a Spigen case as the OP. This is what i figured out. There are 3 categories of ordering a Spigen case:
1) Spigen case fulfilled & shipped by Amazon (iPhone 6 only, not 6 Plus). These were already in stock at Amazon and ready to ship.
2) Spigen case listed on Amazon but shipped from Spigen. These incorrectly said "in stock" on the Amazon site but were correctly listed as "ships in 7-10 days" or ships after "Sep 30th" on the Spigen website. Spigen may not have updated the shipping date on the Amazon listings.
3) Spigen case listed on the Spigen website and shipped by Spigen. These correctly say "ships in 7-10 days" or ships after "Sep 30th" (depending on the case).
The only people who were fulfilled on time were #1 shipped by Amazon. People who ordered from Spigen, on Amazon (incorrectly says "in stock"), had to wait 7-10 days for shipping (correctly says on Spigen website) from Spigen.
I called Spigen and never got a return phone call. I emailed Spigen through Amazon but only got a form letter response (thank you for my inquiry, customer service will get back to you as soon as possible etc). I then got a shipping notice from Spigen the same day as the email response.
Well....
When I ordered my case on the morning of 9/11, from the Spigen website, it said "in stock" and that it would ship in 2 business days.