ICPC Process and De Facto Parent Motion

So I am at the very end of my ICPC process with approximately 3 weeks before it should be completely wrapped up through all the channels and back to California. My husband and I have been active in the process of trying to get placement of my niece since the day she was born. We thought we were at the tail end of our case and that everything was going well. But we get informed that one week before the 6 month hearing when baby girl's father will be getting his services terminated, that the foster parents are filing a de facto parent motion. We have had continued and consistent visitations with her since she was born. She has been with the foster family for 7 months. I do know that child welfare is on our side and is actually changing our ICPC to adoption instead of relative but this is concerning. Baby girl's social worker stated that the ff is doing this wholly independent of the county's interest and should except considerable resistance from legal counsel. Should we be worried? Does this mean that they will now be able to keep her instead of placing her with her family. We are upset as we have bonded with her and feel as though things are beginning to turn themselves upside down. Anyone deal with a similar situation? Any support or things I should possibly do? My ICPC worker wrote a letter for the court for us as well. I do know that the county they are in is very into bio family reunification, but am unclear on California laws.