There may be different numbers of units reserved for different countries, Google being global and all that. I'm in Australia and ordered my Pixel XL (black, 128 GB) from store.google.com. There was no delay processing the order, it took me about 2 minutes to complete.
The phone will be sent from El Goog's regional warehouse in Singapore, same as my Nexus 5 was some two-and-a-half years ago, and estimated delivery date to me is 26-28th October, along with the comment "Processing 1-2 business days + Delivery Standard 3-5 business days". Which sorta doesn't quite add up to 10-12 days, now being 18th October, but I guess it's close. Maybe weekend days don't count.