Not Oxford, but yes, departing VFR, though only because they'd refused an IFR departure when I booked out! (Presumably didn't want to have to stop the flow of incoming IFR arrivals to separate me, as I was wanting the northern SID and we were on a southerly, and I guess I would have had to be separated...)
Oh well. As I said, if I'd done something wrong I'd have expected to be asked to phone the tower, so Lock n' Load is probably right.
Tim