Disclaimer

This is an anekdote when we use the 425 Too Early. It differs from the ietf-425-definition

We have two systems

A) A fast one, legacy, better request seldomly

B) A smothly scaling API connected to a standard database (MySQL)

Whilst the legacy system gets updates within seconds, the API relies on the database, which gets updates from 3 to 5 hours later.

Requesting the API will lead to three different answers:

1. Requested source is already in the database => 200 OK

ELSE: Requesting the general existance of the data

2. Requested source neither in the database nor in the legacy system => 404 Not Found
3. Requested resource can be found in the legacy system => 425 Too Early

No°1, obviously, delivers the full dump of requested data, whilst No°3 only indicates that there will be available data in the near future without specifying the ETA.