EVERY weekend I go somewhere and charge to 100%, and on Sundays when I return, I only top up on strong chargers if there is a little bit left. That will probably be the reason, why your battery degraded so quickly. I'll see how I turn out after years, since I mostly charge only up to 80% and slowly...

Your car should have a 'location' set where the smart charging is effective. When not in that location it shouldn't have any impact.

I think there is some confusion on the Octopus pages about what constitutes a 'compatible' charger.
There are:
1 Chargers that control charging (with any EV)
2 Chargers that don't misbehave when you charge by allowing Octopus to control the car.

I'd say charger every time. At least the charger will be connected by WiFi and have pretty solid comms back to Octopus. I use the car, because my charger won't do and I do get failures when the Skoda app goes down. You need to be careful about describing a charger as compatible - the octopus site is...

Most keys used to resynch if pressed enough times.

I think that the problem is usually that the navigation doesn't know whether you are continuing on the motorway of turning off and approaching a roundabout - it seems to depend on the curve of the road at the time and which is shorter. If you jab the accelerator it seems to fix it.

You can buy a kit to wire in dashcams, that provide a piggy back fuse adapter to pick up the power - lots of videos on YouTube on how to do it.. The wire is easy enough to thread under the head lining, trim, door seal and down to fuse box behind the glove box. Easy peasy.

Sorry - I thought I could see a white 2 pin schuko connector hanging beneath it.

Isn't that a single phase granny charger, so about 3kW maximum?

If you charge overnight at an off peak rate of say 7.5p a kW, why on earth would you want to preheat before setting off at 29p a kW? Because it makes for a more pleasant experience, getting in a warm car and not having to scape the ice off? It gives you more range - how much is your time worth? ......