I've added the picture onto your post from the attachment and I am very sorry to hear about your loss.
I know its no help to you but just to warn overs... KEEP YOUR KEYS WITH YOU AT ALL TIMES... if you go out, take them with you and if you go to bed... take them to your bedroom, don't leave them on the stairs, kitchen side or hanging up where they are easily found.
If people don't know where Bishops Stortford is located then it is North of London.
You may find this car located around your area in a bad estate or still around London. I wouldn't have thought it will be shipped off up North and if it has then they would have changed the plates to an identical looking car. Sometimes they are stole to order also and put into lorries, containters and shipped straight off.
I know this is probably not what you want to hear but knowing the facts sometimes helps things out.
I hope you get it returned, if not then I hope you get a quick and swift payout so you can get another

or different car.
I will make sure I keep a watch out and i'm sure others on the site will also!!!
Keep your eyes on ebay/autotrader/pistonheads and your local papers for a blue

matching your's, even if the reg plate isn't yours!!!