On 18 March, Bank of England minutes were released. The minutes showed that a decision to maintain the current monetary policy was taken unanimously. Also, CPI might decrease below zero in the current month and the strengthening of the pound may affect inflation growth in a negative way. Apart from the minutes, downbeat UK labour market data put some pressure on the British pound as well.
After the news release was published, the GBP/JPY currency pair dropped by 121 pips in 15 minutes, which allowed to make up to $998, with trading one lot!
Bank of England Minutes