For an assignment set to allow resubmissions, all Similarity Reports will be generated again within an hour of the due date and time of the assignment to allow students' submissions to compare against one another within the assignment. This is also known as collusion checking. A change in the Similarity Report's percentage may result from the regeneration of the Similarity Reports if matches are found.
It is important to understand that collusion checking only happens after the due date of the assignment if resubmissions are allowed; Similarity Reports generated before the due date of the assignment will not have checked the submissions within the assignment against one another, but only against external sources (i.e. internet, publications, global repository, etc.).
Although we are confident that papers will be checked against all papers within an assignment upon the assignment due date, we cannot guarantee this. Therefore, any papers that do not appear to have been included in the two-way collusion check will need to be manually regenerated. An instructor can generate a new Similarity Report for a paper by following the guidance here.
Note: Assignments set to generate Similarity Reports immediately, with the first submission being final, will not generate a new Similarity Report on the due date to check for collusion. Individual Similarity Reports can still be manually regenerated by instructors if needed.
More information on the Similarity Report settings can be found in our Help Guides: Additional assignment settings.