Could a treaty battleship reserve space for larger turrets?

Could a treaty-limited battleship use large barbettes with lighter twin turrets, then receive triple or larger-caliber turrets after an escalator clause took effect?

Possibly, but the ship would also need compatible ammunition spaces, machinery, and prebuilt replacement turrets, turning the idea into a substantial planned conversion.

The hull could be arranged so existing turrets were lifted out and replacements fitted later, but the apparent shortcut would shift difficulty into ammunition spaces, machinery, and replacement-turret construction. The larger mounts would need to exist somewhere before the refit, making storage and production a major part of the plan. Fortifications at a naval base might provide a peacetime use for the reserve turrets before they were moved aboard ship. Even so, exchanging the mounts would remain a major planned conversion rather than a quick wartime expedient.