Mothballed shipyards and British rearmament

What if National Shipbuilders Security had mothballed closed yards instead of demolishing and restricting them?

Britain would likely have reactivated major yards during rearmament, gaining valuable carrier, cruiser, capital-ship, armor, and steel capacity.

Preserving the closed yards could allow major reactivation around 1937-38, when rearmament created demand for large warships. Beardmore on the Clyde and Palmer's at Jarrow are the principal examples. Palmer's construction of Queen Mary supports the suggestion that an Illustrious-sized carrier could fit, although the available length would be tight. Beardmore had already built Argus and battleships, while its Parkhead foundry could also help relieve shortages of capital-ship armour. Jarrow's integrated works took production from iron ore to a finished steel ship within one company. Preserving these facilities would retain useful steelmaking and armour capacity alongside the building berths.