You're not following the thread. You would disconnect a single channel approach when visual hundreds of feet up- it would not have happened. You then either turn OFF the A/T (and lose automatic G/A thrust capability) or put A/T to standby ('Speed Off') so if you hit the TOGA switches, the A/T will reactivate and give you G/A thrust! Depending on your airline SOP. If you are not visual by Cat1 limit, you would GA. Well above 27'!
It's flogged to death now!