i think this may be related to iNaturalist’s first 10,000 record limit for API responses (or maybe queries in general?). each of the identification pages gives you 30 records per page. so you would exceed the first 10,000 records starting at page 334.
compare what happens when you try to go to the following pages:
- https://www.inaturalist.org/identifications/dan_johnson?page=333
- https://www.inaturalist.org/identifications/dan_johnson?page=334
(so not really a bug.)