The best thing is to create your own mod and load it after UCP so that your changes are not overwritten if you ever upgrade UCP. Just load it after UCP.

Readme has section ":::: 2.2: Auto Build Queues", which has some of the details. But basically copy those 2 files into your new mod and edit or add to your desires.

Here are the base game key listing:
https://psteamcommunity.yuanyoumao.com/workshop/filedetails/discussion/1109736522/3365901931425883000/

Ah so i can make my own list in the form of a mod, thx.

Is it possible to also instruct the game to delete structures from a colony ? For example, I want to autobuild most prod/food buildings but eventually once the planet is maxxed, I'd wish to sell most prod/food buildings and max research.

Is this possible for an "autobuild" ?

I don't think so, autobuild only adds things to the build queue.