I’m not quite sure what will happen when this first season is introduced, but I’m pretty sure the answer to their “promise” is Icons.
Any Icons that have been saved or not used by the end of a Season will be auto-converted to 10% of their VP value when the new Season begins, giving players a means to get a headstart for the new Season.
At least, that’s one way. Another one to look out for is a monetary solution on the weekend.