Mostly technical analysis, bear flag pattern on the monthly chart for gbp/usd.
For gbp/jpy major stop orders aka money is at 116.8 i dont see banks leaving those lows and moving prices up before they are taken.
https://gyazo.com/6a5a0cd8569da9f9c01eff76cdb76117
All my analysis is saying the yen will be getting stronger across most pairs, its the best safe haven currency as well
also once we drop article 50 that will make the £ shit even more
Disclaimer dont take my word for gospel i am definitely not qualified to give advice