BRP System has from version 2016.5006 released version 3 of it's Application Programming Interface (API).
The documentation of BRP API version 3 is bundled together with BRP Online and can be found at the following URL:
where xxx is a license key that BRP will generate for you.
For BRP support - since version 2017.09.01:
If you already are using BRP API version 2 and would like to use API version 3 you have to use other authentication method using access token. Instructions how to retrieve API v3 access token through API version 2 call be found here: generateapi3token