Need help understanding a requirement for I-130

I was adopted by an American citizen when I was 15. I had residency but only just found out I was entitled to citizenship. It of course lapsed so that opportunity has since closed:( I now want to apply for residency so I can work while I'm here (I'm on an H4 visa). I'm looking at form I-130 and I believe I do qualify but I'm stuck understanding one portion. It says:
"You may not file for a person in the following categories:
1. An adoptive parent or adopted child, if the adoption took place after the child's 16th birthday, or if the child has not been in the legal custody and living with the parent(s) for at least 2 years prior to the filing of the petition."
I did live with my adoptive family for 4 years but haven't lived with them for a number of years now. Does this form mean I have to have lived with them for min 2 years at any point in time or two years immediately prior to submitting the application?

Thanks!

Reading the (American) English it seems to mean living 2 years (immediately) prior to the application.