This rumor created by you is based on a false assumption. Fact: The SP3 released in June 2014 was not replaced just a few short months later in November 2014 but a whole 16 months later in October 2015. Fact2: several new models of the SP3 were released during it's lifetime and like that, the Surface Book with Performance Base is a new model of the original Surface Book not a new generation like Surface Book 2.it means that the new surface book i7 only exist for less than half a year.
I am writing this to you, @wynand32, from my Surface Book 1TB with Performance Base. The ever so slightly thicker base, better battery life, and 3000x2000 screen are perfect. I considered waiting, but I am glad I did not.