Pete Thomas Oh, one other thing I should have asked... did you check the activity log at the bottom of the remote-control page? That should show eco mode getting turned off, even though the portal UI doesn't get updated to reflect it.
On that page in the portal, only one of the modes is allowed to be enabled: eco mode, timed discharge, and timed export are mutually exclusive. So turning on timed discharge implicitly turns off (that version of) eco mode. But then turning off timed discharge explicitly, all 3 modes are now turned off. Except the page doesn't update the sliders to correctly show this.
The fundamental problem (IMHO) is that they are presenting an abstracted view of the real flags, which are the ones you can see on the remote-control section. These are 'enable eco mode' and 'enable DC discharge'. Timed discharge mode has both these on. Turning off timed discharge mode then turns both these off.
It is much better behaved on the app's user interface, and in the portal remote control. The app presents a different abstraction of the two real flags, such that you can only turn off timed-discharge "mode" by explicitly moving to one of the other two "modes". And the remote-control section doesn't abstract it and lets you see the actual registers.
See also
https://community.givenergy.cloud/d/3654-timed-discharge-behaviour-survey
where I tried to describe it in more detail.