A bow with a linked arrow will keep that arrow link even if the arrows are not equipped anymore.
How to reproduce
link an arrow item to a bow item
set the arrow item to carried (not equipped)
the actor sheet will now say that the bow does not have ammo, but if you shoot with it, it will still consume the arrow since the projectileId is still present on the bow.
What
A bow with a linked arrow will keep that arrow link even if the arrows are not equipped anymore.
How to reproduce