Upgrading FreePBX from AAH 2.8

I need to upgrade FreePBX to fix paging issues with Cyberdata IP Speakers. Would I be able to just update FreePBX to the current version (I need the current paging module), or do I need to update to the current Trixbox for it to work? I am wondering if the current FreePBX needs the current Asterisk version for proper operation. Reinstalling the whole Trixbox package would be risky as this is a production system with 25 users and I am concerned about losing settings from AAH 2.8 to Trixbox.

Any thoughts? Should I just bite the bullet and do the whole upgrade?

Thanks.

TB is just a script install of others work, so it really has nothing to do with the freepbx
I have installed 2.1.3 and rc1 on my boxes which are all custom built boxes without issue