If your PHEV only takes 16A (3.6kW) then still get a 32A (7kW) charger fitted because you’ll want that later on when you get a full EV, going for the 7kW version now avoids needing to uprate the cable that runs to the charger from your house electrics & avoids the need to upgrade the charger unit itself although most are simply a bank of 3 dip switches inside to change. Some “chargers” are a little more clever than others & can interact to use cheap rate electricity, but for a PHEV that’s probably not a big concern considering the extra costs involved (Zappi/OHME). This link may point you in the right direction – speakev.com/forums/home-charger-reviews.388/
Thanks for that very useful info Julie. Is it worth me upgrading the onboard charger to 7 kw for the sake of £400?