IDK but MOCF has been working fine with Kaby for many users and in fact I would say compatibility between Skylake > Kaby is perfect as in you can pop one in and they both work the same.
With that being said, Apex is inbound (thanks Newegg!) and I will put it through it's paces and see how it compares to Z170. As long as it's nothing like an Impact I think I will be happy, Impact was complete garbage for me in terms of memory clocking and never have I raged as hard as using that little board.
I mean the fact that you had to bin motherboards on the Impact is ridiculous, there should not be that type of difference in memory oc from board to board i.e. if you take a cpu, set of memory (same order) from one board to another they should clock fairly similarly.
Regardless I think if you have an MOCF it's good enough for most users, but if you are buying a new Z270 board for Kaby it's safe to say the Apex is a no brainer. Looking forward to rebinning all my B-Die on the Apex as memory OC looks strong af