After touching 1.5991 previous high resistance, GBPUSD pulled back from 1.6000, suggesting that a cycle top is being formed on 4-hour chart. Initial support is at the lower line of the price channel, and the key support is at 1.5770, as long as this level holds, uptrend from 1.5602 could be expected to resume, and another rise towards 1.6300 is still possible. On the other side, a breakdown below 1.5770 will indicate that the uptrend has completed at 1.6000, then deeper decline to test 1.5602 support could be seen.
