I got in contact with Fred through a mudlarking group on Facebook. I met him on the beach of Minster on the isle of Sheppey, in the Thames Estuary at low tide, the best time for detectoring.
Fred had grown up in the area and lives nearby. He uses the shipping forecast to get information on the best days to look for finds, the best combination is a spring tide along with high pressure. Exposing areas of the seabed that rarely get seen.