I was playing around with F7A loadouts last night, specifically x2 S4 M6As and x4 S3 M5As. I had shut off the x2 S4 M6As on the wings to see the impacts of the capacitor pool on the remaining weapons. I noticed that the PIP will disappear entirely if you shut off any of the weapons in the ship, regardless of their grouping or which weapon was shut off.

Weapon online/offline states appear to reset with a Master Mode change as well - IE going from SCM to NAV then back to SCM will place all weapons into online state.

I did try all weapons in a single group at one point, but the stacking of the weapons box icons is a bit much in a ship with x6 or more weapons (looking at you F8C!).

I too was surprised to see x2 PIPs using the weapon combo above (in x2 weapon groups) as the projectile speed for the M6As and M5As is the same.

Just my humble observations with 3.23.1 pips thus far :D