[Slick]

WP's and satellites are totally separate. Satellite "stacks" and WP "stacks" are not linked in any way. The only *slight* exception to this is when satellites are unlaunched. They represent another target for incoming damage to the planet; this damage might have otherwise gone toward a WP. IMO using satellites for this is not a very bright idea and unlaunched satellites don't fire their weapons.

edit: note that after the v1.91 patch, WP's are hit before other stored cargo/units.