Please be aware of a change to the way the PPR API handles the callbackURL parameter.
As of version 1.2.5, a callback URL will be used in a search results report request if it is submitted and the response JSON is over 220KB in size, which corresponds to a report of approximatedly 150 pages or more.
Only include a callbackURL in the request if one of the above conditions is true.
This update was necessary to address performance issues with the API. Please refer to apigw-site and the spec https://bcregistry-demo.apigee.io/docs/pprproxy/1/routes/ppr/api/v1/search-results/{searchId}/post for full details.