Hybrid UK owner here, depending on how I (or especially my wife) we can average 37-55. This varies massively due to

Temp inc engine temp
Type of road
terrain
style of driving eg sport, or eco
tyre pressure
load (in if full talk)
gradient
stuck behind HGV/lorry reaping rewards of aero dynamics
do you use cruise control ?
speed limiter ?
are you a heavy breaker
heavy acceleration

If you have any concerns perhaps disconnect battery, reset the mpg and try and couple of constrained tests ?

I haven’t yet found any moments when it feels it’s “in between“.. (have had this on other cars).

 

Thanks

I think there is definately something amiss with the power/revs when even going up a slight incline

 

perhaps with passenger in vehicle get a quick video of it?

 

Absolutely normal. You have an e-cvt transmission, but e-cvt is a bit of an oxymoron because it has only 2 gear ratios. The first is electric mode where the electric motor is driving the wheels. Then there is the gear ratio where the engine is directly connected to the drive shaft...So you actually have a two speed transmission.
Here two a good tutorials on Honda's e-cvt.

 

CVT transmissions are totally different than geared transmissions. They will run in a higher RMP zone commonly when an incline demands more power. Completely normal. 42MPG is excellent for any CUV. It's not a Prius. You're not going to see 50MPG.

 

Unlike the typical CVT with a belt and conical pulleys, the e-cvt in the hybrid doesn't have a belt or pulleys. In fact it has no continuous variable ratios at all. It has two fixed gear ratios one for the electric motor and the other for the internal combustion engine. When the vehicle gets up to approx 60 mph the transmission connects the gas engine to the drive train via a fixed gear ratio. Below 60 mph the gas engine isn't connected to the wheels but is generating electrical power for the electric motor.
Why they called it e-cvt I have no idea, I guess it sounded cooler.

 

Absolutely normal. You have an e-cvt transmission, but e-cvt is a bit of an oxymoron because it has only 2 gear ratios. The first is electric mode where the electric motor is driving the wheels. Then there is the gear ratio where the engine is directly connected to the drive shaft...So you actually have a two speed transmission.
Here two a good tutorials on Honda's e-cvt.

Love those Weber U video tutorials.