Change field value when selecting plan

I wonder if it is possible to change a value of a radio field on the fly when selecting a plan ? I can only find the posibility to change upon plan activation/deactivation, but not upon selecting a plan ?

There's no functionality for changing values on selection. What exactly are you needing such functionality for?

Well maybe I don't It is for a site where users until now have made a selection (Radio field) between being a full og a semi-full member. When activating CBSubs on the site this selection is then gonna be made by selecting the relevant plan - but I suppose that the radio field then might be obselete, when I import the users to the correct plans..

I would just update the field using CBSubs Fields in that case as a fallback until you can remove the need for the field.