There are more than 4.7 million banknotes in the UK with the queen's face on them. They will all be replaced

 The Queen's death has caused a ripple effect throughout many major aspects of the United Kingdom. One of the many components awaiting change in this system is the currency. There are 4.7 million banknotes that are in circulation throughout the United Kingdom, and since they all have the Queen's face on them, they must be replaced with the new heir to the throne. What a daunting task. However, the United Kingdom and other countries that feature the Queen's portrait on their banknotes plan on slowly phasing out these, now, outdated bills with the new heir, King 

https://www.cnn.com/2022/09/09/business/queen-banknotes-and-coins/index.html

Kenny Siwicki