First, an apology; I should have looked at the Bank of England balance sheet, but I haven't bothered for about six months. While I was looking elsewhere, the balance sheet exploded.
The explosion took place during the five weeks between September 10 and October 22nd. During that period, BoE assets went from about ₤90 billion to almost ₤300 billion, an increase of about 14 percent of GDP. It has fallen back slightly more recently, but the total still stands at ₤263 billion.
So what is happening? The Bank of England went from being a central bank to the interbank market. It is taking deposits and other short term liabilities from commercial banks and then lending it back to the banks short of liquidity.
These operations are just one more example of how sick the UK financial system has become. Without the direct support of the Bank of England, it would collapse.