Your conditional green card is valid until March of 2025, so you should file an I-751, divorce waiver, with supporting documents as evidence that your marriage was bona fide by January to be safe. If you have decided for sure on divorce, start the process immediately. When you file the I-751 in January, you might already have a divorce decree, in that case, include a copy. If the divorce is still in process, explain in the cover letter that the divorce process started in May, 2024, and is still pending. The RFE requesting the divorce decree may take a few months, because I-751s take forever to process, so unless your divorce takes more than a year, you should be fine. Yes, you will get a 48-month extension letter after filing the I-751. USCIS will not normally be persuaded by an angry ex if you have good documents showing financial co-mingling and cohabitation since the date of marriage until separation/divorce. Most ROC cases with divorce waiver are approved. Best advice is to get a good divorce attorney. Good luck!