Hi Bill, Based on feedback here in the community and at the Flex dinner in Dayton, APD will happen but it will be after LAN remote. (I searched for APD, pure signal, and predistortion to find some of the threads)
Given that LAN remote is V2.0, APD won't happen in the V1.x releases. It looks like your guess that it will require the $199 version upgrade is likely. So it will happen but not sure when. FRS is not likely to provide a guesstimate or list it on the road map for a while since they still have a number of months until V1.5 is released.