@jrobb @gomerx Most likely, the best bet to keep your instance from attempting to push to identica after the migration is to go through your subscribers list and click “Block” on identica accounts. This should kill off the subscription to your account and stop your instance from pushing to identica. One way to help this, will be to edit ./lib/framework.php, make PROFILES_PER_PAGE greater than the number of subscribers that you have, you can change it back after you are done. Of course, this could have an impact later if there is some sort of bridge. The blocked users will be stored in the table profile_block. Clearing this table should release the block.
I’ll post this to !vivalafederation while I’m at it. ;)
Also, YMMV. @jpope is not responsible for databases blowing up, StatusNet instances imploding, the sky falling or other acts of <insert whoever you like here>.