Would Admiral-class conversions have displaced Ark Royal?

Would building Admiral-class carrier conversions have prevented Ark Royal from being built?

No. Ark Royal would probably still appear, while one or more older experimental carriers would leave service earlier.

Large Admiral-class conversions would not automatically remove Ark Royal from the Royal Navy's later program. The navy would more likely retire one or more older experimental carriers as treaty and fleet choices tightened. Argus, Hermes, Eagle, and especially Furious formed the more plausible pool of ships to release. The counterfactual therefore changes which pioneer hulls remain in service rather than eliminating Britain's purpose-built 1930s strike carrier.