Fußball Club Südburgenland, also known as HOCO Südburgenland for sponsorship reasons, is an Austrian women's football club from Olbendorf, a town in South Burgenland, hence its name. Founded in 2002 after the women's team of SC Pinkafeld decided to become an independent club, it has played in the ÖFB-Frauenliga since the 2003–04 season.
The ÖFB-Frauenliga existed before 2003.
The context makes no mention of the ÖFB-Frauenliga other than that the team has played in it since the 2003-2004 season. It would likely be assumed that the ÖFB-Frauenliga existed before then, which is probably why the AI guesses that, but technically we have no information stating that it did.