For example, we know that airbus has the selector "take off/ go around" so it doesnt make much sense on touchdown with the speed on hold because if you have to go around you will loose time on turn the AP off.But once again i have to say autoland will autoland (lol).
But a "normal " usually the final app is made on manual.
Give you a precise ALT its dificult, because there are so many diferent app, with so many DH, then you have wind conditions.You may turn off AP when you see the runway (that could be 10 miles or 2 miles out). The book say you idle when you have the runway "done" but 90 knots are diferent than 143 knots (737-200 ??).2400 gross weight are diferent than a heavy.All that is important but its up to you sometimes to find the way.
What i do is at 500 feet i set the throttle at 1/4 that will mantain the app speed, at 100 feet i turn off AP (all the features hdg, thr, ) and i start to flare.If this is always the same? No sometimes is diferent.IT DEPENDS.
I hope it helped
