I have a treasured number plate that I have had for a few years, in the past when I have changed it to whatever bike I have at the time, it has not cost me to change the number on my insurance policy, but this time it cost me £35, then they emailed me my new policy details, how can it cost £35. When I took the policy out, I did inform them I have a treasured plate that I would be registering to the bike, the very nice lady said that it won't cost me if I do it within 3 months, which I have done and now they are saying it's 35 quid. when I challenged it, naming the woman i spoke to,  I am getting oh that lady has left and its £35.                                                                                                                                                                              

Tell them to send her the Bill Or phone and ask to speak to her as she is dealing with your problem see if she is still there                                                                                                                                                                              

Doesn't matter if she's left or not. She was working there when she told you it was a free transfer and was acting on behalf of the company. Personally I'd make the payment but ensure you make it clear that you're not happy and intend to seek the advice of the insurance ombudsman. Them having to deal with the ombusdsman will hopefully make them think it's not worth the hassle for £35 and they might just give you an instant refund. Worth a try.
                                                                                                                                                                             

If you disclosed your intention to change the reg number prior to accepting their offer of insurance and in the same phone call, then it forms part of the contract. Any reputable insurance company will hold a record of the call for a minimum of 12 months as anything you say to them also forms part of the contract. If however the conversation occurred after you agreed to take the insurance then it's a change after the contract came into force and you would need it in writing.
While it could be argued that the agent exceeded her authority in verbally altering their standard T&Cs they would be hard pressed to prove it.   

agree totally - stick to your guns on this - they will undoubtably back down at the thought of the ombudsman tramping thru the paperwork                                                                                                                                                                             

I,m insured with mce and they charge £35 everytime I ring up to amend my policy :( and they say they make no money and put or premiums up.... Aaaaaarrrghhh  but life goes on :D                                                                                                                                                                              

Banks and journalists have been rumbled , lets hope its this lot next !
                                                                                                                                                                             

I have paid the £35 and said i'll be remembering it when i have to renew my policy, which i will do.   when i get the the renewal quote i'll be insisting on a £35 reduction on any quote they give me   and i quite agree with you Firetrap !!!                                                                                                                                                                             

treasured plate....the one i just ate fish and chips off.....best plate i saw ,,,70's bloke in frome in somerset had a triumph with TON100...how much for that sucker now i wonder...?                                                                                                                                                                             

Used to have a 350 Velo with FCK 699    Ar kid had a 650 Beeza at the time with 9939 U   So we took great delight passing people as a pair                                                                                                                                                                              

My Plate is R6 SUX                                                                                                                                                                              

My plate ends FKU and no its not a private plate but i think it fits its purpose! lol