HMS Eagle at Singapore and the survival of Force Z

How much would need to change for HMS Eagle to be in dry dock at Singapore in December 1941?

Redirecting Eagle's scheduled refit and equipment to Singapore could put her there, giving Force Z fighter defense and carrier reconnaissance that might radically change the Japanese attack.

Eagle historically went to Liverpool for refit, so redirecting the work to Singapore is a relatively small administrative change if equipment and skilled staff arrive in time. Her presence would add both fighter cover and carrier reconnaissance to a force that historically lacked either. Fulmars could attack the unescorted Japanese bombers, while their radio reports might bring shore-based fighters into the battle. Swordfish searches could also give Force Z better positional awareness before the air attack developed. Fulmars would fare poorly if Japanese Zeros were present, which limits the counterfactual benefit.