Other support at the 50% and July swing low at 1.2928-31 (and that EURGBP too).
The GBPUSD was on the defensive as technical selling and a running EURGBP also impacted the price action (see post here
Technically the price moved up to the 200 bar MA on the 4-hour chart (see green line in chart above) and found sellers.. The tumble lower, was able to push below the triple bottom at the 1.2950 level only to stall ahead of the next target at the July 2017 lows and the 50% retracement of the move up from the June lows at 1.2928-31 (the low reached 1.2938).
The price has snapped back and is trading more toward the middle of the 50%/200 bar MA range now at 1.2972.
Looking at the EURGBP, the pair tried to break above top side trend lines, but momentum faded and that has helped the GBPUSD rebound as well (see chart below).