At about 5 pm yesterday at sydney there was a very large gust front come through, so im pretty sure windshear was the reason for the go arounds. We were arriving at about 5.45 and during a period of 15 minutes our star changed 3 time. 34 then 16 then 34. Then there was heaps of traffic within 30nm of SY being left up high, being off track due to weather diversion. So quite a high work load. We were lucky to land at about 6:10 on our first attempt after the front went through. So i guess the virgin went through SY right in the heart of it.