the GBP/USD has broken above the previous top (dotted red) which indicates that a larger bullish correction is likely. The GBP pair however remains vulnerable and volatile due to Brexit news. Keep in mind that a key Brexit vote on the current Brexit proposal will take place in the UK parliament on Tuesday 15 January 2019.
The GBP/USD seems to be in a wave 4 (pink) as originally expected 2-3 weeks ago despite the lower low (blue line). Price could be in a wave W (blue) of a wave 4 (pink) but the wave patterns can easily change this time due the increased volatility that can take place on Tuesday due the Brexit vote.
The GBP/USD is awaiting a breakout of the trend lines before a major move is possible. A bullish break aims for the Fibonacci targets.