Without a fleet train, the British did depend on their network of bases, but I wonder how much coal or oil they left in these places. To get to Stanley from Singapore, for example would require vast resources, and there’s a distinct lack of British bases in the southeast pacific once you’re past the Cook Is.
That's why it's best to have your fallback plan in the Indian Ocean - you already have the locations in Colombo, Trincomalee, Port Blair, the Cocos Islands, the Maldives, Diego Garcia, and the Seychelles.
It's interesting that in 1938 there was a review that asked the question, "What happens if Singapore is lost?" and the Admiralty's reply was that it would not happen.