It's the end of March. I think the Editing team has all the information they need for this stage, but they are not in a hurry. If you've got comments/questions/ideas, please keep posting. Expect to see a bit more (e.g., perhaps a timeline) in the next few weeks.
On the community side, I think the main tasks will be:
- updating any help pages (if your community has a page saying that you can do something that will no longer work), and
- asking editors with soon-to-be-invalid signatures to update them. In some wikis, this is just a couple of people, and in others, we'll want to use Special:MassMessage.