Hi

1200kWh... so far for February?
Well, for us 60* at -15* works fine... and that's enough even @ -20*.

No... you shouldn't let the house "cool" down and resume heating at full blast in the morning.
Obviously the HT will use least kWh when not working... but try to find a setting for your house when it works longer periods ( maybe even 24/7 at coldest days).
That means, say you set 22* desired temp ( where do you have the controller located? )
Adjust the settings temp at High outside temp say 15*C and at -15*C or the lowest you normally have for your area. Set the temperature out no higher than HT will just keep 22*C or 21.8* ( @ 22.5*C in the house will stop the HT )

You will have a constant heating ( more comfort ) . HT will work with less effort and just "maintain" the tempin the house, without the need to bring it up in the mornings . No peaks... just keeping it steady.

Do you have any temp data for your location... average temp in winter? How many winter month ...
Try out different settings, write down ( log ) the kWh consumption....

Write down what temp outside, what temp HT delivers to the radiators... and kWh used... say average for 4 or 6h...
Good luck