I started doing some research ,and found this post
Boothroyd's Directory of British Gunmakers lists:

A. Hollis & Sons, 28 Victoria, London (no date)
A. Hollis & Co, Mincing Lane, London (1897-1908)
Isaac Hollis & Sons, Birmingham
William & Christopher Hollis, Birmingham
William Hollis, Cheltenham

There is no listing for any Hollis on Minores, London but a Google search found these separate replies to similar queries:

"I traded correspondence about this maker with Boothroyd several times before he passed. Don't know when the style changed, but would like to know myself. Alfred B. is A. Hollis & Son, previously in the Minories, later in Victoria Street, successors to E. Hollis and W. & E. Hollis, established 1796. Royal warrant as gunmaker to HRH Prince Arthur, Duke of Connaught. Also gunmaker to HE the Viceroy in the late 1880's. One or more outlets in India. Geoffrey was quite certain that Alfred's business wasn't connected to that of Isaac Hollis, and I agree."

(and):

"Alfred B. Hollis, the proprietor of A. Hollis & Co, came from the same gunmaking family as Isaac Hollis, the owner of the more well know I. Hollis concern.
While having his origins in the Birmingham gun trade, he was an inveterate traveler, and while in India in 1885 set up in Bombay as a gundealer.
Although he signed his guns “A. Hollis & Co – London”, it seems, despite being a trained gunmaker, he was merely a distributor and repairer during this phase, in the same manner of other India based firms such as Mantons, Lyon & Lyon, Rodda, P. Orr & Son, etc.
He counted among his customer the Nizam of Hyderabad, and the Duke of Connaught; there are some rifles around that carry the legend “Rifle Maker to the Duke of Connaught”
This reference as a “rifle maker” probably explains why A. Hollis shotguns are rarely encountered. Or alternatively, unlike rifles (excepting .303’s), shotguns have been a prohibited export from India for many years."

In my inquiry here and there I had a typo for the street name. It is Minories, not Minores.