OK, I've looked through this now - thanks everyone.
I've also revised my original opinion of an inheritance being unlikely - he's clearly gone to a lot of trouble to keep his original name alive, as if he was reluctant to change it. Even adding Hedges to his dghtrs names is odd - I know about the custom of adding the mother's maiden name but these Hedges didn't do that either.
So I agree now that inheritance is most likely. I wonder if topas37's cousins can shed any light; if the grandparents showed signs of undue affluence? It must surely have been a sum worth having to warrant the hassle of the name-change. I'm also theorising that the benefactor was an "Alfred May" and childless or without surviving sons to make the name-change significant? Or a codicil attached to the original inheritance stipulating that it could only pass to an "Alfred May" regardless of the current benefactor's knowledge or wishes? Just thoughts.
Still finding it impossible to believe that my immediate Hedges had any money to leave I then thought it could have come from a fallen comrade? There's an Alfred John May, solldier, b 1891 in Hartley Wintney in the 1911 census. The only trouble with this theory is that he appears to have been still alive and kicking in 1970!
But returning to topas37's original query to me yes I do have an Alfred Sidney May in my Hedges tree but as he was born 1875 in Surrey, married Alice Emily Lampard in Surrey 1902 and died 1938 in Surrey I couldn't originally see any connection to Poplar or the Isle of Wight until Hartley Wintney came into the frame on this thread because the Hedges/Mays are related to the Priseman's of HW. Harriet Sarah Hedges b 1858 in Lambeth md John Priseman in 1874 in Poplar. He was born HW. Alice Emily Lampard was born in HW in 1882. I haven't done much research on the Priseman family, being so extended from me, but I do remember when I looked at them a few years ago - and there's a lot of them as I recall - other researchers seemed to think they originated from landed gentry or nobility or something. My GG Aunt, of course, married the one who worked as a labourer in the docks!
Last thought, is there any independent evidence putting Matthew in Halifax in 1911 apart from the census? I can see Minnie was there in 1914 to give birth to their daughter but I'd have thought the census for Alfred May b c 1888 in West Ham a more likely match. But he was stationed in Dinapore Cantonment India in Apr 1911 with the W Middlesex Regt (at least I think it says "W"). Is that possible?
Wendy
PS my "Hedges Tree" is public on Ancestry.co.uk if anyone wants to check it out.