I'm not very familiar with this but I ran across this post and was googling the differences between IR-1 and CR-1. (you can tell how little I know) but I did run across this:
"If You Were an LPR and Are Now a U.S. Citizen: Upgrading a Petition
If you filed a petition for your spouse when you were a lawful permanent resident (LPR), and you are now a U.S. citizen, you must upgrade the petition from family second preference (F2) to immediate relative (IR). You can do this by sending proof of your U.S. citizenship to the National Visa Center (NVC). You should send:
A copy of the biodata page of your U.S. passport; or
A copy of your certificate of naturalization"
That can be found here:
https://travel.state.gov/content/visas/en/immigrate/family/immediate-relative.html
I hope this helps...if even just a little bit! Good luck!