A delayed Washington treaty would not revive an Admiral-class carrier

Would an Admiral-class carrier conversion be built if the Washington Naval Treaty were delayed by two or three years?

No. The decisive choice belonged in 1917, well before even a delayed Washington conference.

The proposed Admiral-class conversion belonged to an earlier wartime project, separate from the treaty decisions that later produced other converted carriers. By the early 1920s the relevant hulls and opportunity had already disappeared, so postponing Washington would be too late. Cammell Laird later gained standing as a large-carrier specialist despite lacking an official completed fleet carrier, suggesting that its earlier design work supplied otherwise hidden experience. The chronology distinguishes a discarded wartime project from treaty-driven conversions.