I would be very pleasantly surprised...six weeks before the street date is a pretty long time. Redemption's "This Mortal Coil" came out 10 days after last year's fest and InsideOut/Century didn't break street date, and that would've been hundreds of guaranteed sales to their core fanbase.Fingers crossed for possible early purchase at PP!!! Can't wait for this.
I wouldn't pretend to know the exact marketing strategies that Kamelot and Steamhammer/SPV have in place, but selling it at PPUSA would almost guarantee an online leak*. Yes, it will leak anyway eventually, but - and this is a genuine question, I don't bother downloading leaked albums or paying attention to them - do most albums leak that long before street date? Also worth considering is that the original release date was going to be September, but they pushed it back to October. Whatever the reason for the delay, it was an intentional decision that they likely didn't take lightly.
* That's not a knock on Glenn, the fest, or the vast majority of attendees, but much like bootleg videotaping, all it takes is one asshole.