When using Add Batch > Upload CSV on a place checklist, using a CSV formatted according to instructions, Occurrence Status does not populate from the CSV for taxa already in the checklist, only for new taxa. Description and Establishment Means both populate for all taxa in the CSV, whether or not already in the checklist. But Occurrence Status instead populates from current values in the checklist for existing taxa. It should be possible to update Occurrence Status of existing taxa via Upload CSV, as currently possible for Description and Establishment Means.
Example checklist:
https://www.inaturalist.org/check_lists/1369494-White-Mountains-flora-CA-NV-official-boundary-Check-List
Test CSV:
Bromus rubens,description of Bromus rubens,common,introduced
Bromus tectorum,description of Bromus tectorum,common,introduced
Horkelia hispidula,description of Horkelia hispidula,present,endemic
Polemonium chartaceum,description of Polemonium chartaceum,present,native
Avena fatua,description of Avena fatua,absent,introduced
The first 4 species are already in the checklist, Avena fatua is the test case for a new taxon.
For testing/replication purposes, the values for the 4 existing species are currently set to blank/unknown in the example checklist. Note that to repeat the test, Avena fatua must be removed from the checklist again after each CSV load.
Side note (stealth feature request): currently there is no provision in the CSV format to specify the default (blank/unknown) values for updating existing checklist taxa. It would be very helpful to have that option.