Thank you again for the very helpful input. Regarding where my Arthur was in 1891, I have not been able to find a census record for him in that year. However, in 1881, he has moved to Gathorne Terrace in Leeds, Yorks, where his son, Hadleigh Sydney Seaborne was born. He is trading as a Commercial Book-keeper.
There is also family knowledge of a strong Salvation Army link. His wife, my G-Gran Alice Clara, played the Cornet at some stage in one of the Sally Army's places (but no proof of same). Family gossip is that Hadleigh, his son, was named because of the link to Hadleigh Farm. Also, Arthur & Alice lost a son named William Boothe Seaborne, again, a pertinent reference to the founder of that army.
Regarding the house at 154 Mayall Rd, I have copied a Google image of it as it is today. However, I have no other knowledge of that house or how it was used in that period.
I agree with Millipede, in that I have not been able to find any indication of an overlap between the 'two' Arthurs. Equally, I haven't been able to tie him in to any form of military service, institution of other that might have explained a period of disappearance.
A final tit-bit that my Aunt mentioned and which my Mom also talked about in my very young years, was that he (Arthur) once worked as a Clerk at Australia House and had what both described as 'wonderful copper-plate hand-writing'. There is some evidence of that in my Arthur's signature on the 1911 census, although, I wouldn't go so far as to describe it as such myself. Because of the Australia reference, I put a deal of effort into Arthur Seabornes who might have travelled to Oz, NZ et al, but without any joy.
Sincere thanks again to each for your help. In a way, you've reinforced my own sneaking conviction that the two Arthurs must be one and the same. I was just a little reluctant to accept the obvious, I suppose.
But I'll keep digging anyway, just in case....!
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