What is GA? I don't see GA mentioned on the page, or any words starting with G, does it mean generally available? If so I don't think the abbreviation is necessary.
GA (General Availability) just meant out of "Beta". If you don't see "Beta", you can assume GA unless they word things a bit weirdly and not mention "Beta" but a synonym, such a "limited availability". Just be careful and read the full page, which seems like it's your habit anyway. :)
Correct, it means General Availability. It’s pretty common to abbreviate it (actually, I don’t think I ever see it written out).