A new version of the API will remove the regression-v2 scoring algorithm, but leave regression-v1 in place for now. regression-v2 is a historic scoring method that is discouraged for screening use (it's intended use is internal de-duplication of entities in our database).
A new regression-v3 scoring mechanism is now being developed and will be released, but not recommended for screening use. Any requests that are sent to the API using regression-v2 will be re-written to use regression-v3 in the future.
