PR release workflow-9 Role resolution via user exit.

Hi,

I am creating new release strategy for PR.In existing release group /code combination for some code workflow 9-Role resolution via user exit is set while as for some code workflow 1 is set.

1) I would like to know user exit in which I can see settings / coding done for workflow 9

2) What is difference between workflow 9 and workflow 1

3) How in case of workflow 9 agent is determined.

Thanks & Regards