Thats a real bummer mate. As already posted, hopefully you will get a good comeback from the HPI check.
The last option of the "stolen" bike being an actual ringer of yours could hold some answers??
Apart from your bike being the stolen bike, make sure that the details the local plod have, are the correct ones however unlikely.
Data on the PNC ( Police national computer ) is only as good as the person inputting it in the first place.
Hope it works out for the best mate.
DC.