DanH On the portal (not the app), do a Reset to Defaults on your inverter. This should: disable all timed charge and discharge periods; set the battery charge rate at maximum; and enable ECO mode. To charge the battery from surplus PV during the day and to discharge the battery to meet house load any time, this is the default (ie ECO) setting. Once that's set and working, you can overlay your timed periods. Just check that your portal isn't tied to any supplier automation (ie Octpous).
Set your timed charge period to match your off-peak and then set your Charge to % to whatever value you want your battery at, at the end of the period. During the timed charge period, your battery will charge or discharge to the Charge to % value, and hover around there until the end of the period when it will either charge from excess PV or discharge to supplement PV to meet house load. That should be all you need to do.
If you have/get an EV, which you want to charge during off-peak, just make sure that both the inverter timed charge period and the EV charger timed charge period are the same and neither should interfere with the other.