Analyzing the 4-hour chart, the AUD/USD pair trades below a critical bullish trend line with support seen at 0.6505. A breach beneath this level could lead to notable losses. Moreover, the pair fell below the 50% Fibonacci retracement level derived from the upward movement that started at the 0.6419 swing low and reached a high of 0.6568. This suggests a turning point where traders should proceed with caution.