When will the new iPhone 6 Phablet come out in stores?

Rumours say that the new iPhone 6 phablet will be a phone/tablet. How is this possible?
The new mobile os: IOS 8 is definitely going to come out this fall.

There might be a 4.7 inch iphone 6 and a 5.5 inch iphone 6 and the 5.5 inch one will be a phablet and the 4.7 should come out first in either august or september and then the 5.5 should come out next as the iphone 6s

Phablet is the term coined to devices that have larger than 5" displays. They are still classified as phones but because of their larger screens are almost considered tablet-like, hence the term.

So the iPhone 6 phablet of course is not going to be nor can it be a phone & tablet.

As far as when it would come out, could be mid-September or sometime later in the year.

IOS 8 won't be available until the fall, but you can install it now if you register your device's UDID with a developer account through a site like http://www.udid.in/. It's $5, and then you can try the new OS before it is released to the public. That's how I got it on my 5s.