Right now, JFBConnect only pulls 'in' from Facebook, it does not push out. We're doing some large updates to the whole integration with JomSocial, CB, Kunena (and soon to be other) profile systems. Pushing profile changes to Facebook isn't on our task list for this next update, but if you have more information on how you'd like this to work, we can investigate it more.
First off, what community component are you using? How should the user be notified that changes are going to be saved on your site and Facebook? Is there anything else you think is good to 'think through' during this investigation? Mainly.. we try to always make it so an administrator can't really annoy their users unintentionally.
Hopefully that makes sense, and we can't wait to hear your input!