The initial poster should have spelled out General Aviation rather than abbreviate it to GA. It’s easy to miss such a short abbreviation when reading the post.
As some of you know, I think it’s just laziness or lack of typing skills when people use abbreviations. The correct way, in my opinion, is to spell out the abbreviation the first (or only) time it is used. followed by the abbreviation in parenthesis. This is especially true when it comes to abbreviations that can be ambiguous. “GA airports” can refer to General Aviation airports or Georgia airports.