Dynamic Wrap Up Timers for Asterisk

I am working on a personal project in an attempt to replace an existing custom-built Asterisk application running on an older version (1.4, I think).

While putting together this application I am trying to extend an additional set of functionality, I am working on Asterisk 11 as I already have a working base knowledge of this system fairly well.

I am trying to setup wrap-up timers and honor the global wrap-up timer setting, which I completely understand how to tackle this. What I am doing though is as soon as a call is answered via a Queue I am placing them into a separate conference room with the two people via AGI (that way the agent and the callee are in a conference room to bring in 3rd party members).

My problem now is that after this happens they are no longer being honored by the wrap-up timer rule setup. My question is if anyone knows how to dynamically set the wrap-up timer counter for an individual extension? I have eyes on the conference room via a daemon so I can easily reset the timer once all parties have left.

Is there a way I could achieve this with the current working base or is the wrap-up timer something that is handled internally and unmodifiable?