We've had this conversation before. General opinion is that you will be able to listen to the BBC Radio 3 broadcast on the BBC iplayer - it's BBC Prom 25 Grainger. See if it works - you've still got six days left. If it does work, you should also be able to hear the Cambridge Folk Festival Highlights on BBC Radio 2. However, you will need a specific program to watch the TV broadcast of the Prom.