I have a 2 complete set red and yellow and 1 red/yellow wild property
You are free to reconfigure your card sets any way you like on your turn.
Rules:

You can only reorganize your property collection on your turn.

You start a new set (since both of your red and yellow sets are already full), but you can start that with either the new red/yellow wild or one of the red or yellow cards from your existing sets (and put the wild card into that set to replace it).