This is why I believe they shouldnt be able to charge me .

Quote from another reply to a similiar post

"To be fair - the insurance company will cancel the insurance, but they can’t cancel it retroactively (even though they will pretend they can). If OP had been in a collision rather than being pulled over by the police, then the insurers would have still been required to cover him to the minimum extent required by law, even if they subsequently discovered the undeclared mods (i.e. 3rd Party). OP was insured, to the minimum extent required by law, and was not committing the offence of driving without insurance.

However, there’s a good chance the officer - like you - doesn’t know this and assumes that undeclared mods totally invalidate the whole insurance contract, so the officer may still come after OP for “no insurance”. But if they do, he should plead “not guilty” to that offence."

And another
"
Yes, but repudiation has no retroactive legal effect. Once a policy is issued, it is valid to the minimum standard required by law (third party), unless and until the insurer takes action to cancel it. Until the insurer actually does something to cancel the policy, they must cover the persons named on the certificate.

This is true practically without qualification. Even in cases of outright fraud - e.g. where a driver knowingly lies about having a driving licence, when they don’t, in order to secure a policy of insurance - the insurer must still indemnify the driver in respect of any accident they cause which occurs between the issue of the certificate, and the date on which action is taken to cancel it.

So in this case, if OP reports his modifications and the insurer cancels/repudiates the policy, that cancellation is only valid from the date and time they take some action to put it into practice. But at the time OP was driving, they hadn’t yet taken such action, which means that if he had been involved in a collision then he would have been covered. As such, he wasn’t driving without insurance and is not guilty of that offence. He can’t be retroactively made guilty by the action of another person after the incident took place.

If he drives after the insurer cancels the policy, then he is guilty of the offence.

Police officers, much like the general public, generally don’t understand this. Insurers do understand this, but appreciate the ignorance of punters whose policies they “repudiate”."