The only place I know of that “repurposing” is explained is on this forum, in random comments.
For example:
But for some reason this does not apply to murals:
And property owners can request repurposing!!!
There is a topic in Wayfarer Basics which does have a comment addressing this, too, about updating Wayspots.
This is, of course, not an exhaustive list of all the places on the forum where “repurposing is not allowed” has been mentioned.
(lol am going to stop editing in examples now)