The following photo was posted on a well known Tug Discussion Group site:
. . . . . and the following comment:
RE - Picture Added: WATCHFUL
Posted on 04/07/2003, by George Robinson
The name WATCHFUL has been used by HM Customs for patrol craft and the last one I know of was built by Dunston at Thorne in 1951 ... I have a photo and it's not this one, but maybe she is a pre-war vessel which was replaced by the new one in 1951? These HMC vessels tend to go unrecorded, have asked Philip Simons who is good at these but he has no info. on an earlier one. So just another theory ....