This just started happening today- if I filter overall identifications simply by ascending instead of the default descending I see the old things first. If I refine those records for example to show Unknown, it bounces back to descending (newest first) order, despite the url still being in the form of
https://www.inaturalist.org/observations/identify?iconic_taxa=unknown&order=asc
System is Win 7 Chrome Version 73.0.3683.86 (Official Build) (64-bit)