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Per Wikipedia, In April 1941 Percival was promoted to acting lieutenant-general, and was appointed General Officer Commanding (GOC) Malaya.

Who was the best British general to command the defence of Malaya? Better choices are likely found amongst the Australians, like General Blamey, but IMO the British would never give supreme command to a non-Brit - though I'm open to being convinced otherwise.

So, we need the new general to arrive in April 1941. It can't be a senior general, as they wouldn't be in direct command of Malaya, but would instead be a supreme regional commander, likely based in India. So we're looking for a lieutenant-general or lower ranked general or thereabouts, same rank as Percival.

Some options:

https://en.wikipedia.org/wiki/Edmund_Ironside,_1st_Baron_Ironside
https://en.wikipedia.org/wiki/Claude_Auchinleck
https://en.wikipedia.org/wiki/Henry_Maitland_Wilson

This old thread isn't much help https://www.alternatehistory.com/forum/threads/alternatives-to-percival-at-singapore.321340/
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