Strip wax
Ask the Expert featuring Mike PhillipsDiscuss Strip wax in the Detailer's Library forums; Do you guys strip wax before applying a new coat ? If so , how do you do it , what products ?...
Flash a bunch of dollar bills at it? Oh wait that's how you get something else to strip....
Does the paint look ok? Does it need any polishing? Mike Philips is all ways saying he doesn't know of any wax/sealant that can hold up to a compound/polish.
Other's here I've noticed use a heavy soap concentration and 'wash' it off.
Waxes and Paint Sealants wear off naturally via wear-n-tear plus through micro-abrading when you wash the car, this just means there might be less than you think.
It's important that the surface is clean before applying applying any kind of non-cleaning wax or sealant or otherwise you can seal in contaminants.
There's some information here in this article on this topic...
I polish/clay my dds twice a year, once in the spring and once in the fall. Depending on paint conditions I use the appropriate polish, ie, paint cleanser, finish polish, moderate polish.