Best answer by Duppy
Welcome to the community
The availability and timing for smart meter fitting, is not something that the community can really help with, as PP are fitting SMs according to area and fitter availability.
Pure Planet have only 1 tariff, and looking at the Octopus Go the tarrifs for charging at night are really competitive at around 5p per kWh between 12.30 and 4.30am.
It would appear that you don't need a two rate smart meter as octopus take half hourly readings, so will know when and how long the vehicle is on charge, and price accordingly. It also states that it works better with a smart charger, but I don't think that is compulsory