Small business rates

[Bathsheba]

Hi everyone. I posted this earlier today in Business + Finance, but maybe this is a better category.
Our accountant has recently informed us that we are eligible for small business rates relief as our premises have a rateable value under �5000. The council claim they wrote to us in 2005 outlining the new law, but we definitely didn't receive a letter. They've now informed us that they will backdate a claim to April of this year only. Anyone got any ideas where we can go fom here? Clearly the accountant is at fault here for not letting us know sooner, but we want to keep him onside for the time being.Any help much appreciated.