Hi Nozz,
Uhm, well brokers - we all live and learn.
As you still have proof of sending and can ask the post office for a copy of the signatory (think it costs £2.20) I would do that tomorrow morning first thing (assuming you have a debit card). You can check also (on line) when the letter was delivered.
www.royalmail.co.uk
Then call Adrian Flux (surely they get the mickey taken all day long) and state that the policy should not have been cancelled. They received the letter on XYZ date and you are requesting copy of the signatory from the Post Office. As the error is their fault you expect the policy to be reinstated immediately and for any break in cover you wish to be compensated. You will not accept any fees which they may wish to charge you as it is all their mistake.
Be firm. Get the persons name you are speaking to and also if they get stroppy or denign every receiving your post, state that you require the managers name and direct phone line number and you will be contacting the Financial Services Authority immediately.
Any problems, come back to me and we can get a letter sent to the board of directors!
LOULA