PANface this is definitely a downside to solar and batteries on IOG whilst export rates are good. First world problems, although I suspect those days are numbered, duck curve, zonal pricing, blah, blah.
Anyway, realistically, your options are:
1) don't plug in until the sun has mostly gone
2) switch off smart charging and set a timer in the appropriate device to only use the core hours (you only need to smart charge once a month to pay lip service to the T&Cs) Not really in the spirit of things but, here we are.
3) depending on how you're integrated to IOG, leave smart charging on, set a timer in the chargepoint/EV for say 21:00-05:30 and plug in anyway. The danger with this method is you get insufficient charge because half the slots Octopus generates are outside of your defined period.
