As I now have a connect box, I changed the power saving mode on my Horizon box to ECO as I no longer use it for internet or landline access.
According to this link, scheduled recordings should still work in eco mode:
However, a small amount of testing shows they don’t.
EDIT … I’m going to do some more testing as I’m sure an earlier recording did work despite the box being in standby. I’ll post again in a day or so.