The meaning of the plane numbers on the flight deck

[Mykhal]

I was wondering if anyone would be able to tell me what, in game, the number beside your rocket/torp/bomb squadron symbols actually represent?

In most cases, I think it is supposed to represent an attack wave within the squadron but in some cases (such as Implacable torpedo bombers) it seems to represent individual planes.

Anyone know which it is supposed to be?

[_Blink_Blackwolf]

Assuming I understand your question properly, that is the number of planes of each type you have in reserve. 

For example, Hakuryu has 24 TBs in total. So by default, it'll show 24/24 below TB icon. If you select that squadron to deploy, the number will become 12/24 as a TB squadron takes 12 planes to form and rest of the 12 are still in reserve.

Pressing "Alt" will tell you how much time left for a single plane to be restored(in case of a plane loss)

[Mykhal]

Ah, I see now. Did not know about the 'alt' key feature

So left alone, the number shows progress to a full squadron and the Alt key shows the flight deck capacity and the timer countdown.

Thanks for the help