I have been informed that US Chess will note on the cover of any new rulebook printings that the 7th edition is the 2020 version (updated 11D, 11D1, typo fixes).
The e-book edition will reflect those changes plus an earlier update makes the index linkable. To get your free e-book update Jon Haskel says: If one logs into their Amazon account and goes to “Manage Your Content and Devices” then “Content”, one will find all their books that have an available update. One just clicks on the “update” link and the book will be updated automatically. Be aware that getting the update means any bookmarks or notes you created in your current version will disappear.
The on-line version for 1-1-20 (chapters 1-2, +11) will also reflect the rules changes and typo fixes.
And US Chess is working on e-mailing affiliates and TDs regarding the rules changes for 1-1-20.
That is the most up-to-date info I have come across so far (12-14-19).