AUDUSD has recently extended its downward trend, falling from 0.6894 to as low as 0.6622. As long as the price stays below the falling trend line on the 4-hour chart, the downside move could be expected to continue, with the next target being the 0.6594 support level.
However, there is also immediate resistance at 0.6685. If the price manages to break through this level, it could rebound back towards the falling trend line on the 4-hour chart.