If you pick a FOSS license then your project is FOSS. The number of developers doesn’t matter.

I moved all my (meager bullshit) personal projects to Codeberg awhile ago. My stuff was already open source, but I did explicitly add some license files I neglected to add before just to make it clear. So far so good.

Before you archive your Github repos make sure to update them with one last commit explaining that the repo has moved to somewhere else (and potentially why). Once you lock the repo you can’t make changes. If you straight-up delete them then this isn’t an issue.

I had a dog who developed seizures. Low dose phenobarbital solved the issue thankfully. It was a little inconvenient because he required regular liver tests and also, phenobarbital being a controlled substance, I had to buy it at a regular pharmacy. But other than that it was fine, much better than the seizures. He had no issues until he died (years later) of unrelated problems stemming from old age.