Motorway or running fast use HEV mode, try and keep EV for local or 30/40mph , ideally you want to return home with a depleted battery.
With a PHEV when the battery is over 80% you will gain nothing from regeneration, I run my battery down to about 50/60% that way I get maximum regeneration, a depleted PHEV gets maximum regeneration, hence why these HEV are so efficient.
It took us a few month to get the best out of the PHEV it is a learning curve.
Unfortunately I have suffered a brain injury and occasionally I get confused and often say the wrong thing.