No it won't - this is an urban myth, and the contrary (i.e. your insurance IS valid) has been upheld by the Insurance Ombudsman. Insurance
may only be invalidated if the vehicle wasn't roadworthy, and that factor of roadworthiness would have been picked up by an MOT.
The rest of your post is fine.
Tom - Only speaking for myself here, personally I would not consider driving with an expired MOT.
The prospect and thought of being involved in a serious car accident, then is attended by the police.
The checks then discover the car is not currently carrying a valid MOT.
Then facing the prospect of a prosecution is clearly not great.
Being dependent on the insurance ombudsman to find in your favour in court, can be very risky.
If they did find in your favour, the insurance company could be facing the cost of the claim.
So, is this likely to happen ???.
Depending where you search, the answers on this topic does differ in some aspects.
Here is a quick example taken on the subject.
What Happens If You Drive Without An MOT?
The consequences of driving without an MOT varies depending on the severity of your offence.
As mentioned previously, if you only drive without an MOT to the testing centre and can prove this to the police, they cannot fine you but will probably suggest you do not risk it again.
If you are pulled over by the police and cannot produce a valid MOT certificate or proof of an appointment, they are within their right to fine you up to £1,000. In the very rare occasion, if you genuinely forgot your renewal date and are only a day or two late, you might just get lucky and given a warning.
1. Your car failed an MOT test
It’s possible that your car fails a new MOT test while a current certificate is still valid. If this happens and no ‘dangerous’ problems are found, you
CAN take your vehicle away for repairs and return at a later date for a full or partial retest.
2. You missed an MOT test
If you have missed your test and your certificate has expired, you
CAN be prosecuted for driving without an MOT.
The info below has been taken from the RAC website and suggests that "certain" insurance companies will NOT provide cover and that owner should check with them.
3. Can i drive my car without an MOT if it is booked in?
Yes, you can drive a car to a pre-booked MOT test without a valid MOT certificate, even if it is on
SORN and doesn't have
car tax.
The vehicle must have insurance and you should check the policy is valid for driving without an MOT, as some insurers may not cover vehicles under these circumstances.
There is no law on how far you can drive a car without a valid MOT to a pre-booked appointment, but you should try and keep the distance as short as possible. Otherwise, if you are stopped by the police or involved in an accident, then you may still be could still be prosecuted for any defective parts on your vehicle.
There is an on-line MOT reminder service which is a helpful for some people.
Sign up to get free reminders by text message or email a month before your MOT is due
www.gov.uk