Yes, once you have signed the Open Banking services contract, you will receive credentials to access the Developer Portal.

Here you will find Sandbox APIs that you can use to verify that the integration with your systems is correct. The Sandbox APIs are identical to live APIs, but they return fictitious data, so you can test the interaction in complete confidence.

Once you have finished testing with the Sandbox API, you can update your application by replacing the URLs of Sandbox API with those of Live API, and you can request the production of your app.