We are very sorry for the negative experience you had and udnerstand how shaken you must have been. As discussed at the time and with the police, your group did leave the back door unlocked - unfortunately, on this ocassion this led to the very unlikely circumstance of a bulglary occuring. Indeed, this is the first time I have ever known this to happen in all my years in Oxford.
I am pleased that the response was speedy and, as you said, we have now changed all the locks in the home.
Again, we want to highlight to any future guests how rare this and the importance of locking doors and closing windows when in an urban area.
We hope you will not be too discouraged from returning to beautiful Oxford.