Every company can choose what they want their uniform as. White shirt and trousers are just a traditional way which most airlines have adapted to. However, airlines can choose to make their pilots wear whatever they want. I think there's an airline which pilots who work there wear a brown shirt? Instead of white
You might have also noticed some airline's epaulettes are in silver bars whereas most airline's are in gold/yellow.
An airline may choose to design any uniform they want their pilots to wear. Sorry if I've answered your question incorrectly, I stand corrected in the info I've posted.
Capt. J (Still a newbie
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