This isn't a bug report, but a question. Can you upgrade an existing FREEPBX install that is currently configured and running? (I understand that you would most likely need a maintenance window). Other wise can it be safely done?
The data is not just in the tables. It's splattered across numerous text files that already have different, but necessary entries. But make a backup and try your hand at it. Let us know what you learn.
I built a brand new PIAF system, and I successfully got the core things over, extensions, sip trunks, ivr, time conditions, time groups, ring groups. My next step is to make a script to automate the work. The steps I took was to run a backup on both the new and old systems. I then extracted the mysql-3.sql from the old system and only included the items I intend to bring over, replaced the mysql-3.sql in the new backup with my stripped down version from the old backup. Did a restore and I was in business.