I'll be explaining this during the webinar (which your teacher will get an email about soon). But basically if you get chosen for space-flight a few minor modifications are made to your code to make it obey the Astro Pi MCP (Master Control Program). As part of those edits, if I see your code is using hard coded two-line element telemetry
lines I update it to load the telemetry from a shared location which is kept up to date by our ground station in Switzerland.
So you can expect to be able to computer accurate ISS locations when your code runs.
I hope this helps!