Now re-floated. Met new member to show him the moorings and decided to check out the work boat.It looked pretty bad but the mud was only to the transom and about 4 feet inboard.
After sliding down the mud bank in the dinghy we got to work with shovels, being hampered by a stream rivulet running by the side then into the boat. One pushing the water away and one clearing the mud, we gained on the problem then we noted a taught rope from an old mooring snagged over one of the link pin brackets that were used to join these boats together to form river crossing ramps by the army.The snag was stopping the boat from rising. Snag cleared, and the tide came in and up she came.Job done. Photos later.