well Alec this is what happened at our club last year, 2 members scanned their rings to put on their youngsters, and did not erase training, on marking night, all birds went through ok, how ever when the clocks were taken off, these 2 members birds were recorded, but no times of arrival, got in touch with Unikon reps and explained, and outcome was, because training had not been erased, arrival times did not record :-/