I am sure a new camera is in the works, either P1 directly or from the Mamiya team. doesn't make sense if they are not doing it.
This is evident from the obvious patch up work on the DF+, the rumors, references; and recently, when P1 said they would offer investment protection on all of their new backs, but not on the DF+ camera. suggesting they are expecting significant depreciation on the bodies once the new one comes out. Timing wise might be a few months after the refresh of the Leaf backs.
I would love to see a waist level finder, smaller size, better build, faster AF, and long expo settings to match the capability of the IQ260. And in general, SEXIER looking please!