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It will have been signal cloning I was wrong in my original post. They were on camera walking round the back of my house.
The key was kept in a faraday pouch, obviously they don’t work you can get box versions which are supposed to be better. Or some people recommend keeping keys in a microwave. I should have had a steering lock on though.
The above being said, as I have had 2 break ins already in the space of 2 years it really wouldn’t surprise me if had they not been able to access the key they would have broke in the house to demand them which wouldn’t have been great as I live alone.
One decision I do make in life is not wearing high heels. Not only are they impractical and uncomfortable but I want to be able to run, fight and defend to my best ability when out if need be, not be limited by footwear and flimsy clothing.