Free sync or Adaptive sync however you wanna swing it can be achieved on DP 1.2. The only reason why it isnt is down to the monitor itself. DP 1.2 already have the core feature of adaptive sync available, its just not been put into a standard yet which likely means that previous to 1.2a there were no unified way to access the abilities of what adaptive sync is going to offer. AMD only had to flash the firmware of a monitor to make it support their prototype run of Free sync, and that was a monitor with DP 1.2 NOT 1.2a. But ofcourse this doesnt mean that the vendors will roll out firmware updates to their older DP 1.2 models if it means they can just sell you the same monitor with DP 1.2a and a firmware update. Hopefully some hacking of firmware will be possible for some of the current models out there.