The Standard prefix was applied to all sizes as I understand it once they started to use that moniker and etch instead of roll impress cylinders late in the first period (and their guns also lost the steel butt plate so the stocks were like the post 1919 guns with a wood bolt acess cover).
Even in Knibb's book it's confusing as he say's Standard pattern for both .177 back to 1906 for .177's to differentiate from Light, Junior etc. and obviously later Military. Then he says "Standard pattern..Improved model D"
Hence say on a Light pattern in the 1930's it will say; The BSA Standard Air Rifle.......177 bore (no. 1), and the same on a 43 or 45 incher etc. obviously with .22 bore (no.2) as applicable.
So re-visting this after a dekko at the book, it seems even first batch rifles were called Standard Pattern in there, so I give up
ATB, Ed