Percy has used some technical language there that suggests some experience.
Keeping quiet seems reasonable, but don’t complain if it comes to light and the bill goes up
Our neighbours, who had an extension before the banding was done are above us. We’ve just had an extension, and loft conversion but it won’t affect the banding until we sell, I think the council can re-band then.
You don’t get penalised for improving the value of the property (unless there is ever a national rebanding exercise while you are still in it). There will be a marker against the property that your purchasers solicitors should spot when they do searches and then warn the buyer that it may be rebanded.
I work alongside the CT banding team. They really hate it when someone appeals their banding and the review means it – and all the neighbouring similar properties – actually need rebanding upwards rather than downwards, especially as GDPR means they can’t say who triggered the change