That used to be the case for me, and so my charge strategy was simple - charge overnight to 100% every single night to maximise the possible feed in. Unfortunately, since 1 January, the cheapest Off Peak is now about 50% more expensive (in VIC) than in 2019.
That means now that the strategy should be to use solar to charge, discharge into peak (obviously), and off peak as well (to minimise the charge at the beginning of the day) to avoid feeding in (if that energy could have been used instead to offset off peak).
The final piece of the puzzle should be never to charge off off peak and then discharge into it; if the algorithm decides to charge (i.e. because the forecast is for a cloudy day), it should go into standby (until peak) instead of discharge back into off peak - charging and discharging into the same TOU band simply costs you round trip losses.
