A 1923 Italian battleship program could accelerate Littorio

If Italy designed a new 28-knot battleship in late 1923, would the Littorio class be built faster?

Yes. Recent design work, an active construction base, and retained yard infrastructure would shorten the path to Littorio.

Completing a new 28-knot battleship with eight 15-inch guns in the late 1920s would leave Italy with recent capital-ship design and construction experience. The yards would retain infrastructure and knowledge that otherwise had to be rebuilt or recovered. Littorio could therefore move from design to construction faster than it did historically. The acceleration comes from industrial continuity rather than from simply copying the earlier ship.