Why seaplane tenders were not the historical Atlantic answer

Could seaplane tenders and their aircraft have been put to greater use in the Battle of the Atlantic for better anti-submarine coverage?

Not with Britain's historical fleet and basing network: there were too few tenders and suitable operating locations, though a prewar MONAB-style program could have changed the starting position.

Britain lacked enough tenders and suitable bases to transform Atlantic air coverage. The question then becomes whether a prewar program inspired by the later Mobile Naval Air Base, or MONAB, concept could have created a different starting position. This keeps the argument focused on institutional preparation rather than treating a few existing ships as a missed wonder weapon. The counterfactual asks what a deliberately built system of ships, aircraft, personnel, and support doctrine might have achieved by 1939.