Some autos are controlled by ECUs meaning they are cleverer than others, more simple ones simply have a kickdown switch on the throttle somewhere and just change up at a set point.

There are ones where you can have it just in drive, or do it yourself, yeah, but manual valve bodys dont do that, you do it all yourself.

My only problem, ive noticed with the C4 is top gear is 1:1, same as a cossies 4th, a bit low for me in an ideal world