I had an chat/email conversation with Nick Tieder from US Frontiers about this.....he indicated that supplies/merchandise had already been sent to Amazon weeks in advance and confirmation of them actually receiving them too. But its Amazon's stupid-ass computerized logistical programming that is messing things up with shipping.......
So in turn, Amazon has the cds, well in advance, its their computer systems that are all F**Ked up and messing up the shipping dates.
Another reason was alluded to was that Amazon is not "checking-in" the cds into their systems after receipt of the cds, and it is causing a huge delay therefore forcing the shippment change dates.

Note: ALMOST every single Frontiers' cd pre-order I have through Amazon.com has never arrived on release date or within 1-2 days thereof....they ALL have been pushed back at least 1 week, most 2 weeks.