User blog comment:Shinhwalee/Guide to Power Leveling Heavy Cruiser (CA) in World 3-2A/@comment-112.198.64.29-20150331134743/@comment-84.90.161.45-20150331234214

I'm no expert on the subject, but here's my opinion:

The flagship should always be restocked on ammo for maximum firepower at all times.

The CVL should recieve at least ammo to restock missing planes and keep firepower up.

The SS can recieve fuel to maintain some evasion, though she will be pwnd anyway at red morale.

The other escort should recieve at least ammo to keep the firepower up and help killing enemies.

Failing to do so may result in A or B ranks, because the flagship alone can only kill 2 enemies (3 if going night battle, but that increases ammo consumption) and low ammo means low firepower ... at red morale it is already hard for the escorts to hit and kill the enemy, take out their ammo and the only thing they'll be killing is your time and patience (and resources).

They could probably do 2 or 3 runs without resupply, but when you do resupply them the amount will be as if you were resupplying after every run ... your call.

Since it's just one node grind and only one ship will be taking the hits, I think that you can skip on the fuel resupply.