Ignition Advance - already at 13 degrees BTDC?

[Seca-Seca!]

Hey guys. In the US here, been researching doing an ignition advance when I'm ready to put the Kat back together. However, this sticker on my frame says it's already at 13 degrees BTDC (see pic). The sticker also says that the bike meets US 1996 new vehicle emissions requirements...

Everything I've read around the site has said the US bikes should all be 4 degrees stock? What does the average sticker say for bikes in the US?

1996 GSX600F

[92xjunker]

Some bikes did come already advanced, European models are.