Well Singapore airlines have no seats between Adelaide and Singapore in the week before Christmas or New Yr and there are no seats from 16-25 Jan from Singapore to Adelaide due to people returning for school. If you can get to Singapore there are seats between there and Manchester and also Paris and Amsterdam ( you could easyjet from there). Depends how desperate you are. There are 3 flights daily from Perth to Singapore and there are seats before Christmas. There are also seats to Singapore from Melbourne before New Year.