OP, careful what you post in the forums. Moto doesn't like it when people they've sent soak invites out to blab about it, so if they catch you they may ban you from being a part of soaks indefinitely or permanently.
That said, if there's a soak coming out soon I think it's way too early for it to be Android N. How can Moto/Lenovo have a build of N ready if it hasn't been released yet? I'll bet that it's either security or bug fixes, or maybe even WiFi calling, which would be awesome.
A very outside and unlikely possibility is that Moto/Lenovo/Verizon are releasing a non-Nexus N beta program, like what Sony's doing with the Xperia Z3, but I highly doubt it.