Does your PHEV default to HEV mode when you start up, or did I misunderstand?
Mine defaults to EV mode (which for me at least makes more sense)
Hybrid mode has two distinct operations:
1: Starting from a full, or nearly full battery the regen mode is active, permitting the car to add juice to the battery from correct driving technique and regeneration itself. Driven properly, this can restore SOC to a car being driven. Yes, this is normal hybrid mode!
2: However, once the battery depletes to a certain level (15-20% or around the blue bars on the battery meter) the recharge mode changes to a simple hybrid mode that restores only the juice to the level needed for that 15-20% battery level and no more.
You are clearly depleting the battery to this level, and therefore massively losing out on the cars actual capability!
Perhaps to make things simple we should separate these into `Hybrid Modes 1 and 2`as this is clearly something that is not being understood..?
Hybrid Mode 1 allows for full recovery of the battery system (if driven properly) whereas Mode 2 allows recovery only of the basic level to enable continued use of Hybrid Mode 2 but locked only to it's modest level.
YOU DO NOT drive straight into consumed battery level (Hybrid Mode 2) as the level of recovery and usage can be far greater, and repetitive if you DONT. Mode 1 is the use to be aimed for.
So it follows that if you travel from A to B where you exceed the plain electric range and accidentally or deliberately allow the car to drop into the Mode 2, you will not benefit from additional battery capacity or restoration of SOC. I have demonstrated this to be worth about 20 UK MPG difference in average mileage on UK roads, and NOT counting short local journeys that can be electric-only. This is far from a one-off electric benefit - consider it as the gift that keeps on giving.
Reading the manual explains this quite clearly.