My findings are similar to the previous replies. If you use the heater/aircon or demand a lot of power (lots of acceleration, climbing hills, high speed etc) then the range drops noticeably. If the weather's warm and you can live without the heater/aircon then drive gently - maybe use the ECO button to soften the accelerator pedal response, then you should see nearer 30 miles. If you put it on charge every night use the heater timers to get it to run the windscreen demister for 10 minutes before you set off. That does draw power from the battery (about 2.5kW), but it'll also recharge from the mains whilst it's doing it so you won't use as much (or any) to heat/demist the car when you set off.
But remember, this isn't a pure EV car, it's a hybrid so you should expect to use petrol at times (especially on journeys longer than 20 miles). Also the predicted EV range will go up and down depending on how it is being driven before you switch it off. It's best not to get too obsessed by the prediction and trying to get as far as possible on pure EV. More useful is how far you get between filling the petrol tank each time.