No. It is submitted as part of your PR application, after you receive an invitation to apply (ITA).
Note that it is only required if you have answered YES to one of the statutory questions in your application.
Is it necessary to submit it with the post ITA application if you have a "yes" in statutory declaration? I thought they request for it depending on the applicant's case.
they will request it as long as you answer yes to any question, not on a case by case scenario.
That's why people submit it voluntarily to save some time