The journey settings.savingProgress fields were renamed: savingMode is now mode and supportedVersion is now supportedRevision. The old names are no longer accepted on POST/PUT /v1/journey/configuration and are no longer returned by the v1 journey configuration endpoints (breaking)
settings.savingProgress is now also supported on the v2 journey configuration endpoints — accepted by POST/PUT /v2/journey/configuration and returned by GET /v2/journey/configuration/{id} and the v2 create, update, and patch responses