GBPUSD stays within a downward price channel on 4-hour chart, and remains in downtrend from 1.6339, and the fall extends to as low as 1.5630. Further decline is still possible, and next target would be at 1.5550 area. Resistance is located at the upper line of the price channel, only a clear break above the channel resistance will indicate that the downtrend from 1.6339 has completed, then the following upward movement could bring price back to 1.6500 zone.