[Also available on Reddit.]
If you are looking for guidance as to how USCIS will decide your I-751 ROC petition if you are separated or starting divorce proceedings, but the divorce isn’t final, then you need to read the Neufeld memo. It’s only 3 pages and worth a close read.
https://www.uscis.gov/sites/default/files/document/memos/i-751_Filed_%20Prior_Termination_3apr09.pdf
