I sent them the letter (by hand) last Monday. Today I got a phone call from HSBC saying
"I have just recieved your letter" (! 8 days after I handed it in)
And
"We need to know a breakdown of where you got the figure from"
"All the bank charges in the past six years"
"Yes, but we need you to tell us where you got this figure from. Can you send them to us, please..."
Your thoughts?