When do you stop eating suhoor? When the fajr adhan is given or when the white thread appears? In Australia, the adhan is given much earlier than when the white thread appears that is why I’m confused. Can you please clarify?
You take suhoor till fajr time which is when the white line appears horizontally in the sky. If you are able to decide the true time of fajr then you follow this time and take suhoor till fajr time regardless of the time the adhan is. Because if the adhan is wrong then we do not follow it, and what is more important is that you need to determine the correct Fajr time for fajr prayers. Try to discuss this issue with a trusted Islamic center where an expert can help you to determine the correct sign of fajr.