I'm a long time player and that might be messing up my ability to learn new things.

I was of the understanding that when a character with super strength picks up an object, they must continue to carry it until it us used in an attack or if super strength is lost. In the most current PAC, super strength is optional. Can a character then simply turn off super strength and drop an object for cover from ranged attacks?

It is optional in that you do not have to pick up an object with it. However...

SUPER STRENGTH (OPTIONAL): When this character moves as part of a move action, power action, or free action, it can pick up an object as a free action and carry it. The object must be either in a square the character occupies or in an adjacent square. This character can use an object it picks up as a weapon. If this power is lost or countered while this character is holding an object, immediately place the object in the square this character occupies. This power can’t be canceled while this character is carrying an object. When this character...

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