I’m changing my car today (about time I hear my friends say, the present one we have had for 7 years).
I rang the insurance people to organise the change of cover.
I was asked “What time do you want the change made?”
I said about twelve clock.-“but does that mean I am not insured in the new car at five to twelve or in the old one at five past?”
“That is correct”, she told me.
“But surely, my open comprehensive policy will cover me in the new car?”
“That” she informed me “only applies when the car belongs to someone else, since it would then be yours, you would not be covered”

Thanks for your help Hibernian.