All:
There were two community webinars on 22 January announcing "Public Comment Enhancements" (this and the other changes in the above document). See
https://www.icann.org/news/announcement-2015-01-16-en. The announcement of the webinar mentions the "suspension" of the reply period and the new 40 day minimum period.
Aside from the webinar announcement, I don't believe there was a formal announcement to the community of the change in public comment periods. As a result, there still seems to be some lack of knowledge of this change.
I hope this helps.