It doesn't look like any of these MCC events are registered with UKA/RunBritain. Nor does there seem to be any evidence of proper course measurement.
So do them as a fun run, but don't be surprised if they are long/short.
The Norwich Half, quite rightly, disqualified at least one runner last year for running as somebody else.
Try contacting the organisers to see if there are any cancelled places you could pick up.
Failing that, try another race as suggested above. There are loads around at this time of year.
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