Following call from RNLI, NCI confirmed sighting of one paddleboarder in Estuary, although four seen earlier. ILB launched with request that NCI contact them on Ch.32 with further updates. Three further paddleboarders located but unable to contact  RNLI on Ch.32 or Ch.00. Advised HMCG accordingly. Paddleboarders later safely ashore. NCI Lookout Tower visited by RNLI to confirm use of Ch.00 in future.