I think it'll still need that approval you mentioned but looks like they are expecting changes in terms of throttling the calls per day, etc - if we keep it to < 150K per day, that will solve the problem (so late updates/updates over days) ~
Case Status API – Production Features & Capabilities
The following are available in Production:
- Live receipt numbers are supported.
- Staging Receipt Numbers are not supported.
- Quota is limited to 150,000 daily and resets everyday at - 04:00 UTC (Midnight EST).
- API concurrency limit is set to 10 transaction per second (tps)