I will be ordering an iMac Pro system that has to be configured, but want my credit card to be billed on or after a specific date. The Apple website gives estimated delivery dates, but not billing dates. As I recollect billing occurs at time of shipment, when given to a shipper such as Fedex. So if I want billing, say, to be on or after May 10th, how many days do I add on to that for transit. I.E., if it takes 5 days then I order for May 15th: Ships May 10; billed May 10; arrives May 15. So for folks who have already received system that were not off the shelf and had to be configured, what was your transit time?