To get the "finished at" date, you can use the next API listed in the API User Interface under the collection update history endpoint mentioned earlier.
To get to the API User Interface, you can click "View API UI" under the System menu in the Funnelback Administration dashboard.
The direct link to the API UI, depending on the domain name, is:
https://{funnelback-server}/search/admin/api-ui/
The API endpoint to get the update 'finished at' and status is:
GET https://{funnelback-server}/admin-api/collection-info/v1/{collection}/update-history/{updateTimestamp}
An exit code of zero indicates a successful update, and a non-zero exit code indicates a failed update.