This is very specific but there may be something in here that helps someone else with the same problem, or parts of it.

Setup:

1. Octopus Energy

2. Hypervolt Home 3 Pro charger, installed by Octopus

3. Fox ESS Solar and house batteries (20kw), with Emergency Power Supply (EPS) to run the house in case of a power cut

4. Skoda Enyaq 85x Sportline

Solution for a successful overnight charge:

1. Octopus app: recognises the car, but its smart charging is set to off. Stops it confusing the

2. Hypervolt: Set to "plug and charge" on the Super Eco mode which uses surplus solar power, but is manually switched to scheduled charging in Boost Mode in the small hours if the car needs a charge.

3. Fox ESS: Mode Scheduler set to Force Charge the house batteries from the grid at 500 watts per hour at the same schedule as the Hypervolt. This stops the Hypervolt draining the house batteries to charge the

4. Skoda: charging location set to home (otherwise it won't charge at all), charging method set to "charge immediately" with no schedules set in it. This lets the Hypervolt do the work.

It took a few days to work this out, but I got there in the end.

For anyone who's interested, there's a more detailed write-up on my personal blog.

@Aspman weren't you having issues?