When WW1 ended, only the Household Troops ( Guards and both Cavalry Regts.) retained wearing Dress uniforms - everyone else stayed in Khaki. Dress uniforms were usually purchased by Regiments for the Bands - and maybe some other high profile events. There were some stuttering attempts made at Coronation times - to get the rest of the Army into these "Blue" uniforms - but they never really got off the ground - due to the "Bean Counters" doing their work. My first rifle was a Lee Enfield 303 ( lovely weapon that) - though we changed them for SLR's (7.62mm) sometime around 1960, I think.
Our "best" uniform was the khaki Number 2 outfit - bizarrely worn with a Number 1 Dress Cap ( which WAS issued) - which can actually look quite smart. Summer Dress was shirtsleeve order ( You took the jacket off and rolled your sleeves up and took your tie off!). Working dress for most of the time was combat suit trousers and a Wooly pullover - beret and boots. Hot climates we wore Khaki Drill - with either long trousers or shorts (depending on the insects about!).
I was in the Royal Signals Mike, (Sergeant Radio Operator), and passed through various Divisions Regiments and Squadrons - as both regular and reservist. We always called ourselves the Gypsies of the British Army - as I was always on the move. I finally left the reserves, in 1981.