I have completely full boxes in HGSS, and many boxes of pokemon in my other gen 4 games. I would love to move the pokemon all the way up eventually into Pokemon Home via Pokemon Bank, but really dislike how the met date is changed to the date of...
I was able to extract my save through following advice from these two threads back in the day, given what you've said is this the thread you were referring to...
What's weird is that they both have about the same speed in bandwidth but the Comcast one feels laggy like click something and it takes a second to load, the Eero one is just instant lol