The buyers were given the opportunity to push the GBPUSD higher and they could not do it (see chart above). So the pair rotates back down to see what lies at the 1.5831-40 area where the 50% of the range since January 26th and the 200 day MA are found (at 1.5840).

There should be buyers against the level. However, a move below, should solicit some additional Friday selling. I would not fade such a move – unless it fails quickly.