T i m wrote:

Anyone care to put that into user friendly terms please?

It's never off, just think of it as a frost-stat at all times when you
don't set higher required temperatures ...

e.g set 20 for 7am to get up, then 15 for 9am after you leave the house,
18 for 5pm when you return and 10 from 10pm for overnight, then you can
boost it by the odd degree or two for the odd hour or two as required.