User blog comment:DaNASCAT/Technical Update: January 6, 2016/@comment-4129195-20160107194911/@comment-5383971-20160110232858

Yes, the date-based pagination was replaced with a page-based one, this means no longer possible to navigate through images by date by changing URLs.

If there's demand for finding images by specifying dates, we may want to add such filtering. We decided it's safe to drop it for now (to simplify the UI), because much less than 1% of the Special:NewFiles users end up anywere beyond the first page (this includes anyone modifying URLs by hand to achieve the date navigation).