The WLTP test profile is rather limited, short drives, no hills and constant temp environment. Probably somewhat informative for very urban use cases only.
The new WLTP emissions test should make it easier to achieve your car’s quoted MPG figures
www.carbuyer.co.uk
"......The new WLTP laboratory test cycle is longer than the NEDC cycle in both time and distance - cars are now driven for 30 minutes and around 14 miles......"
From the Defender article - "....Max towing capacity for the P400e comes in at 6,613 pounds, a marked downgrade from the 8,201 pounds and 7,716 pounds that the regular 3.0- and 2.0-liter versions can tow, respectively......"
The batteries are heavy. Which is why LR has said BEV is a poor choice for larger vehicles.