British carrier training without Great Lakes ferries

Which British ferries could be converted into training carriers, and where could they operate safely?

Britain lacked ferries large enough for the American conversion model, already trained pilots across the Empire, and would most plausibly place any dedicated lake carrier program in Canada.

No British ferry was large enough to duplicate USS Wolverine or USS Sable directly. Britain already operated a substantial Empire-wide pilot training system in Canada, South Africa, India, Australia, and elsewhere. If a protected carrier-qualification site were still desired, Canada's Great Lakes would offer the same geographic advantage used by the United States. Training capacity depended on a network of schools and locations rather than the conversion of one particular hull.