Odds of TPR Moving Forward?

Totally new to foster adopting as I am (maybe) taking in our two nieces. My question is that the 18 month review is coming up. Biodad is sober five months, and is now dating and living with his drug counselor from rehab. I am happy he is sober, but he is one break-up away from having nothing done on his plan really as she is the one with a home, transportation, job,etc. Think they will change the goal back to RU-it is adoption right now? Think the judge will see that way his situation is not truly "stable" an move forward with adoption? Another extension granted? Biomom out of picture. Just want some insights from those that have been there, done that. THANK YOU!