Is it possible to save some charge by running on fuel only until later in the journey?  

Yes and No.

There is an option to set manually the charge level which shall be maintained.

Unfortunately it is working very poorly, and it can drain 1-4% at one trip. If it having any positive charge, it will consume it immediately. 

You can force the petrol engine only if you put it in sport mode and shortly kick the gas pedal every time, when it stopping the ICE. After a while the car recognize your will and stopping the ICE more rarely.

Edited 11 February, 20251 yr by mykos

Thank you Mykos