The 15-inch variant draws on the unrealized three-twin-turret proposal for Scharnhorst rather than inventing an unrelated battleship. The scenario assumes both mountings use the same barbette diameter and supporting interface. A conversion can therefore lift out the triple 11-inch turrets and install twin 15-inch mountings in their cradles. The work remains substantial, but it is bounded compared with rebuilding the hull around a different turret system. That makes conversion of a surviving 11-inch ship before Operation Berlin plausible within the scenario's standardization rule.
Notable Point · 2:39:24-2:40:13
A common barbette makes 15-inch conversion possible
The scenario assumes the triple 11-inch and twin 15-inch turrets share a barbette interface, allowing a surviving hull to be rearmed without redesigning the ship.