White-haired Witch, Multiple Grapples and Final Embrace

[Katydid]

Assume you have a White-haired Witch (or other class) with a prehensile hair natural attack with reach equal to or greater than 10', Combat Reflexes and the Final Embrace feat.

My understanding is that any enemies that approach within your range can take attacks of opportunity and be grappled as a free action as per the Final Embrace feat and therefore Grab (Su). Is the free action grapple applicable only after successful attacks, or can the character maintain multiple ongoing grapples as free actions?

[Vertexx69]

This is what my group pulled on me with my WHW. Since your hair is occupied with the 1st grapple that you did on your 1st turn, you can't make AoOs with your hair while grappling with it because the only free action you can take on a turn other than yours is speaking. IE you can't "Let go" of the 1st target when its not your turn to attack the others, because dropping something is a free action. Also even if you aren't grappling something first, you can't grapple as part of an AoO because its a free action as well, and so can't be used on another target's turn.