charge price changed from now on

It is now more and more public charging stations that had been free of charge now are changed to wear a price tag.

I'd like to continue using the zero price in the past, but from the time of changing price the then relevant price shall be used to calculate the price at this charger.

because if I change the default price at a charger, all past charging sessions are recalculated to that new default price.

please make sure as well to include options like

- price per minute

- starting price (start is 1€)

- price per kWh