Lots of boats on the system don't display licences. Lots of boats on the system display licences that our out of date by some months. A few display licences that are a few years out of date, but recently I discovered a boat displaying a licence that must be some sort of a record.
Just north of Braunston on the North Oxford we passed a dilapidated, but floating, GRP cabin cruiser displaying a 1997 BW Licence. Is this a record for the oldest licence still on display? Sorry I cannot provide photographic evidence, it was difficult manouvering past the boat since it was moored close to a partially collapsed bridge.