Trouble is, we all know that people tell little fibs, even on important documents. It could be that the father may have been dead to him, rather than actually dead. (How old was the father when he died 1831...If he's the one born 1876, might he have considered a first child in a will?)
Also, the father was said to have died before James married in 1919 so if true, may have occurred any time after the birth of James.
Stephen could have even been the mother's maiden name. The previous searchers 9 yrs ago even suggest the lad may have been informally adopted by his caregivers. It would be nice to find something concrete, but even with a forename like Oliver, we might as well be looking for a John.
Yes, true but it's that odd he said the name Oliver and Postmaster. There must be a link even though he might not be his father. I think the family he lived in with in 1911 in Drumnahoe had links to a post office via James Sinclair Black and his wife Maggie. Defo no DNA links with the though. I need a crystal ball !!