Durham Substitute Personal Statement Deadline question?

Durham originally says on the website that you need to submit the substitute ps within 3 days of your application getting acknowledged, however yesterday I called through their phone service and got told that the deadline doesn’t matter- send whenever.

Does this mean that even if I send it 1-2 weeks later, Durham wouldn’t have already viewed my application by then, looked at my original ps and automatically rejected me due to an unsuitable og ps? How would they know I was meant to provide an alternative personal statement?