Yeah, I know. THis sucks. I wish the Errata would get done and released. Sorry about that
Anyway, grandfathering is probably gone. The people have spoken.
The new rule will basically be:
1) If something that costs Nuyen or karma changes, you either earn additional karma/nuyen (if prices dropped), or you have to pay the additional karma/nuyen (going into debt if need be and paying it out of your next run reward or two).
2) If something costs essence changes, adjust essence accordingly. If you cannot legally have that essence, you can upgrade to Alpha/Betware if you can afford it, you can downgrade it, or your can remove it (getting a refund in cash and essence).
3) For anything more drastic, you can rebuild your character from scratch, keeping your earned mission awards.
This covers all the major bases.
This is tentative, of course. And hopefully we won;t see major errata changes from here on (Hopefully with new books, we'll have the FAQ ready when the book launches so we can catch anything before players have the chance to update their characters and we need to backtrack).
Bull