I think you have some confusion.
OFF - mains power is off, either because the unit is not plugged in to the mains, or the switch is off at the wall, or the switch on the back at the unit is in the off position. There is no activity, the unit cannot record when scheduled.
STAND-BY - the unit is in its sleep state, there is no activity, a small timer processor monitors for an "on" signal from the remote control or pressing the power button on the front panel, or wakes the unit into a "half awake" state when a recording is due to occur.
ON - the state in which there is full activity and TV output.
"HALF AWAKE" - recording or preparing to record when the unit would otherwise be in stand-by. There is no TV output but the unit is otherwise active and able to service network communication with the WebIF.
The user has no control over the "half awake" state, except by scheduling a recording. There is a fault which can result in the half awake state, but this is not advisable.
The bottom line is: if you want to interact with the WebIF you need to turn the unit on. You can do this manually (by RC or physically pressing the front panel button), or by setting the ON/OFF timers in the settings menu (do not set an on without an off, or vice versa), or by scheduling a reminder. You can also set on/off times using the Remote Scheduler. If the unit is in stand-by there is nothing you can do (from the network) to cause it to wake up, you just have to wait until it is next scheduled to wake up (including half-awake).
All this is very obvious to old hands, but quite tricky to explain in writing.