system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5:IF I give a bank enough time, could I withdraw £1 Million in cash from them?
gpt
Yes you could.

For large sums like that, which they might not have on hand, you would have to tell them in advance so that you could pick it up.

They don't 'legally' have to do anything. Their obligations to you are determined by the contract you signed when you opened the account.