My sources "Shore Establishments of the Royal Navy" and navalhistory.net suggest BRITANNIA II was a Trawler Base from 06/1940 until 23/12/1942.When it was renamed DARTMOUTH. Home to Belgian motor fishing vessels BLANCHE MARGUERITE and CONSCIENCE.
I would suggest that H D EGDGCOME came back to the RN as a Reservist and was at BRITANNIA II as some kind of Instructor.
What bothers me however, is the last record of him was 31/12/1941 , when he was recorded as being Superior for Efficiency and Very Good for Conduct. The rest of the record seems somewhat "clipped"
Did he leave the RN in 1940/41 to become a civilian instructor?
If he was still domiciled in Averton Gifford. which is not that far from Dartmouth, Would he, given his RN service, be treated at hospital in Dartmouth?
Pure speculation.