Lovely Roy - thanks for posting. I particularly like the 1912 Lady's Model, with its bolt-on inlet manifold and skinny tyres.
Re the dates: The middle photo shows mosty pre-WW1 bikes from Douglas, Scott, Clyno, Rudge and others, but one of the bikes in the top photo is a Ricardo Triumph (four overhead valves), so we must be in the early 1920s.
Cheers
Leon