It's not like it hasn't happened at least twice before (see #15 in my FAQ above). Also, it really isn't unusual in projects for that to happen - even actually having to go back and redo work already marked as complete. Thirdly, as
Chaos_Alfa states - progress, in this case, isn't actually going backwards... it just will look like it, based upon the percentage because they are going to try to better define how much each of the remaining tasks contribute to completing the tech update - rather than all tasks having the same percentage, no matter what amount of work is involved. Finally, if you are a subscriber - you can stop at any time, if you haven't already. If you're not, like me, you are scammed out of nothing.
Now to wait and watch the further posts of others who will come in to whine/bitch/moan/complain that they won't be getting their rocks off for free anytime soon. Even though many posts in this thread have repeatedly reasoned they shouldn't expect anything earlier than Spring 2024 - if not much later.