Since as I understand it, the people at t-firefly have been pretty helpful towards getting the RK3288 EOMA board put together, I figured I would point out that they have just launched a crowdfunding campaign to build a RK3399 development board.
I'm not sure if that rk3399 processor would be able to work for a future EOMA68 design however, if it did, it would bring some cool advantages. It looks like it supports USB 3.0, it is a 64-bit processor, and like the RK3288, it can support 4 GB of memory.