AEDT vs EST — cities and working rhythm
Australia's east coast — Sydney (financial), Melbourne (corporate HQ / media), Brisbane (mining / education). Business hours 9 AM – 5 PM AET. Summer: AEDT (UTC+11); winter: AEST (UTC+10). Brisbane stays on AEST year-round — so Sydney and Brisbane are 1 h apart in summer, same in winter. Almost entirely opposite of European hours.
US East Coast — the reference clock for US business, Wall Street, US law and consulting firms, most Fortune 500 HQ. Business hours 9 AM – 6 PM ET. Note: EST is the winter offset (UTC-5); EDT (UTC-4) is the summer offset — "ET" is the year-round non-committal way to refer to this zone in scheduling apps.
Time gap: EST is 16.0 hours behind AEDT (standard-time offsets — daylight-saving flips shift this by an hour twice a year in most northern-hemisphere zones).