Well, I never knew I was still a permanent resident any longer, but after travelling to the US with an expired green card I found out I am! Apparently you can't get rid of it too easily, and I am glad for it.
We left the US years ago for me to go to grad school in Canada. Between being a parent, along with COVID restrictions and part-time work my PhD has lasted nine years. (!) But the border services agent in Vermont told me that I needed to file a series of forms, starting with i-90 for my expired green card, and then either 1-131 or N-470. It's wasn't clear to me which one, and I wasn't convinced he was 100 percent clear either. In the end he said to file 1-131 and that I would have two years to file for naturalization - which I now realize I must do if we are to ever travel to/live in the US again over the long term. But it seems that you can only file the I-131 from the US.
Does anyone have any information on whether that has changed since COVID? This is very stressful as we are planning to go back for a family visit this summer and I don't quite know which route to go.
Thanks!