I have a GL which has steering wheel buttons but no conventional auto selector between the seats, instead it has a stalk on the opposite of the steering wheel to the multifunction stalk (indicator, wipers etc.).
You cannot change gear using this stalk you have to use the buttons.
For the bulk of the time I let the auto do its own thing. However, there are times when I like to select a gear, usually as I’m waiting to overtake, or sometimes for a bit of fun along a winding road. Kick down is too slow.
Using the buttons there are two possibilities to do this; (a) a single pull on the left button causes a down change of one gear, so using repeated pulls you can select the optimum gear,
or (b) pull and hold the button for a couple of seconds and the optimum gear will be automatically selected.
Both of these engage a mode (effectively manual control) whereby the selected gear is held within the engines rev range, a higher gear is only selected when the engine runs out of revs. This higher gear is then held etc.
To cancel all of this a single flick on the column mounted gear lever restores normal auto mode. You can of course change up using the other paddle.
The only drawback to this if the wheel is turned it can be quite tricky to find the buttons.