Sync to Google Drive failed (since update to firmware 4.0)

Dear Boox team,

I only just noticed that since I updated by Boox NoteAir2 to firmware 4.0 all syncs of notes to my Google Drive have failed. Manual syncs result in the error: Sync to Google Drive failed: com.google.api.client.googleapis.json.GoogleJsonResponseException: 404 Not Found. 

I am logged into Google and can view the contents of Drive on the NoteAir2, but it will not sync to Drive.