I have a couple thoughts.
Neither the presence of the Early 2013 rMBP on the Refurb Store nor its 30-business-day shipping time is indicative of the timing for the Haswell refresh.
For starters, the 13" Early 2013 rMBP was available on the Refurb Store months ago. I know this, because I ordered one for my niece's graduation in May. Only the 15" Early 2013 rMBP is a new addition.
Also, products aren't necessarily added to the Refurb Store only when they're about to be updated. The October 2012 Mac Mini was added to the Refurb Store in January, for instance, and is without an update eight months later.
This isn't the first time that a refurbished item carried a 30-business-day shipping estimate, either. That same October 2012 Mac Mini? When it was first listed on the Refurb Store in January, it too had a 30-business-day shipping estimate. Here's what's interesting: Most people saw theirs ship within a couple days, so evidently in that case (and several others, you'll find, if you Google ""Apple" "Refurb" "30 business days"") Apple used a 30-business-day quote as a placeholder or at least a REALLY conservative estimate.
I'm curious: Has anybody ordered one of these 15" Early 2013 rMBPs on the Refurb Store? If so, is yours marked "Prepared for Shipment" or "Shipped" yet?
If the Haswell rMBP is on sale on September 18, I'd call it a coincidence, but I wouldn't blame those who think that there is something to this rumor for feeling vindicated.
For what it's worth, my bet is that the Haswell rMBPs come out in October.
Best wishes to all, whether your gratification comes instantly or delayed.
UPDATE: And just like that, shipping times have been updated to 1-5 business days.