I can't help with the Ilfracombe connection, but wonder if I may suggest a possible Heming family.

You have probably looked at them and they may well be a red herring, but have you considered the Heming family of Wick (not far from Bristol)?

William Harrington Heming marries Lucy Hinton in 1873 (Bath reg dist).

In 1901, their 'son' Maurice is with them born 1896. The GRO reg reveals he was illegitimate (registered as Hemming, no mother's maiden name).

I believe Maurice is baptised in Wick but not until 1900. His mother is shown as Clara Annie (William and Lucy's daughter).

When he marries in 1921 in Wales, he gives his father as William Harrington Heming.

William H H's occupation varies but any of them could be connected to coach building e.g. carpenter. He dies in 1911.

Could Adelaide be an illegitimate daughter of Clara? I have not found anything to substantiate this, though.

Clara marries in 1907 and dies in 1909.