What Britain's experimental 16.7 mm AA gun might add

How would the early war change if Britain's experimental six-barrel 16.7 mm anti-aircraft gun worked?

It would add useful close-range fire and might occupy part of the Oerlikon's role, but it would not by itself solve fleet air defence.

A working 16.7 mm weapon would likely increase short-range volume of fire. It might fill some of the role later performed by the Oerlikon, especially against dive bombers. It would not be a decisive answer to air attack because its effect would still depend on range, fire control, and the density of mounts.