Hi Gavl,
It's my first day on the forum after our discussions with the powers that be in relation to sponsorship and after seeing your post thought we could also lend a hand.
Within this thread you mention that your policy has ended, which if this is the case then there should be no problem with their supplying proof of NCB to you as they are obliged to do so.
You mentioned that you required 4 years but they we confirming 3 years after expiry. With this in mind did you begin the policy with 3 years NCB and cancel before the policy ran the full 12 months?
If so, they would be correct as you would have to complete the full 12 months to earn the extra year with them.
Whilst we have not dealt with Frizzels directly (other than to contact them for NCB on behalf of our new customers) our experience of their parent company (LV) is really positive, they've been friendly and helpful in all dealings with them.
I'll PM you some contact details that will get you through to their Bournemouth head office.
Kind regards
Tony