Press OK standby scree

I just got connected with uverse yesterday and noticed a really big niggle - how in the heck do you disable the standby timer?!  

I can’t find it anywhere.  I leave it on for my dog whilst i’m away and having the TV on gives would-be intruders another reason to reconsider my house as a target.

I’m having a difficult time trying to work out why att would intentionally prevent its customers access to adjust such a feature.