Ship upgrade procedure?

[wga8888]

It is 3/2/42 and as the USN I have a few CVs that are eligible for upgrade 3/42. Rules state I have to move them to a port with a Shipyard (Seattle, SanFran, LA, SanDiego, Pearl, Sydney, Melbourne, Colombo, Bombay). When does the upgrade start? 3/1; 3/31, any day in 3/42 when it shows up and disbanded in port? How long does do upgrades take? Does the ship become unavailable for a period of time? Showing up as a reinforcement in that port?

Not much detail found in the rulebook.

[Ian R]

In general terms the upgrades involve incrementation of the AA, and impose a few sys damage on the way.

Some are bigger - the early 42 upgrade removes the useless 8" from the Lexingtons and substitutes 5/38 twins, a few more sys damage, but a most useful improvement.

The clock runs monthly; disband them on day X on/after the 1st of the month, and subject to existing damage, the upgrade occurs on X+1. The new armament is in place with some sys damage. DDs suffer up to about 13 pts sys damage, larger ships less. As to existing damage, carriers need to reduce it to below 5, in very general terms, for the upgrade to happen.

Make sure you have 4 x AR, 2 x AD in any shipyard port you run an air combat TF to for upgrades/yard time. And preferably a naval HQ.