I laid out 9 packets, which take us to when WotC optimistic timeline calls for (which does suggest that 11 or so packets is their initial gameplan), and leaves ample time for Crawford's less optimistic 6 additional months of repeat testing before they begin finalizing publication, which will probably be somewhere in June-October of 2024 (the range in which 3E, 3.5, 4E, Essentials, and 5E dropped in the yearly schedule).
to lay it out more clearly, in no particular order:
1. Warrior Group Packet, with more Feats, maybe Spells
2. Priest Group Packet, with more Feats and Spells
3. Mage Group packet, with more Feats and Spells
That probably gets us through to the end of 2022
4. The stronghold/home-based Packet, maybe with more Feats and/or Spells
5. Encounter math and Monsters
6. Revisit of the Expert Group, with all Subclasses and any revisions based on the first round
7. Revisit of the Warrior Group, with all Subclasses and any revisions based on the first round
8. Revisit of the Priest Group, with all Subclasses and any revisions based on the first round
9. Revisit of the Mage Group, with all Subclasses and any revisions based on the first round
So that brings us to about August or September next year having covered everything theybhabe committed to, with nearly a whole year before the final publication. And Crawford foresaw followups taking through to February or March before testing is finalized, which leaves ample time for getting to the printer.