That time conversion makes no sense at all. The parts where everyone else were must move waaaaaaaay slower than the outside world and upper draconiums time is waaaaaaaay faster than that. If HanBins group was experiencing time the same as the rest of the world then one year outside is close to 300 years inside.....if it's only been ten years outside that's 3000 years inside....way longer than the age of any dragon inside should be. The whole island must be pockets of wildly different time scales