Sunderland flying boats in US Navy patrol groups

What if the US Navy had contracted for Short Sunderland flying boats before World War II?

Sunderlands could have reinforced Catalina patrol groups as heavier, more durable attack and anti-submarine aircraft.

A hypothetical prewar American purchase would place a Sunderland squadron alongside several Catalina squadrons in a patrol group. The Sunderlands would take the heavier combat role when the group encountered opposition. Their larger size and resistance to machine-gun fire support that assignment. Ordnance could be moved from internal stowage to external release positions, allowing another load to appear after an initial attack. The proposed group would retain the Catalinas alongside the heavier aircraft.