Exchanging old style £20 notes

[cashquestion]

For many's years I've been stashing £20 per week in my house, in safe places dotted around.
They are all the older style paper notes, and now the new plastic ones are coming in I guess I will have to exchange my old ones at the bank.
The money is legit, I just don't trust not having enough cash in case of emergencies, and I've paid tax on it (I'm PAYE).
Assuming I don't have to spend it all buying loo roll on the black market in the next few months, how can I exchange the money without the bank asking me lots of money laundering questions?
I can't really prove the money hasn't come from drugs/people trafficking, but it hasn't, I promise!
I want it back as cash, not in the bank.
Anyone know about this?

I work in a high street bank. We wouldn't swap those notes for you, we'd require you to pay them in. We'd also probably report you for benefit fraud if you get any, as a lot of people keep cash at home rather than in their accounts to stay below the threshold for certain benefits.

Also, you do realise if the cash was destroyed or lost at home, insurance does NOT cover cash?

Do you keep it in a safe OP?

If something happened to you and the police, paramedics etc or anyone went to your home it wouldn't be passed onto your family

You want to change them and then carry on stashing thousands in your home ?

That is really not a good idea. Thank your lucky stars this crazy plan has not bit you on the arse already and get it it put in a bank

Not on benefits done I have a reasonably well paid job, never been out of work, touch wood!