Switched Power Feed For Radio, Fabia Ii.

I fitted an aftermarket stereo with BT and DAB to our roomie, but its going back soon and being replaced with a last of line Fabia.

On the Vroomster I had to add a wire, to activate the radio from the key in switch since normally the signal is on CAN. However as I can't find a thread that suggests this is common, I wondered if on most models there's a switched supply already in the connector, rather than just the permanent feed.

Or is there another option?

BTW I did search, but the search engine seems particularly rubbish at the moment.