We are using the Canvas API to create assignments for courses that have been set up in our 'parent' Exams system. We have 2 types of students : Visiting & Exchange, Standard. The 2 types of students are enrolled in 2 sections : V&E and Standard.
The V&E students often have different assignments to the rest so, every time we create an assignment we set "only_visible_to_overrides" = true and create a Section Override for the right section so that V&E Students only see their assignments and Standard students only see theirs.
If the submission date of the assignment is changed in the Exam system then we use the Edit Assignment API to change the date(s) - due, lock, unlock. We also set the new dates in the Section Override.
What I have found is that, even though the Edit Assignment Request has "only_visible_to_overrides" = true, the response has "only_visible_to_overrides" = false.
The Assignment in Canvas now has an Everyone Else section which wasn't there before. If I query the assignment via the API, "only_visible_to_overrides" = false. If I delete the Everyone Else and re-query it now has "only_visible_to_overrides" = true.
Question: Why is the API creating this section? Also, why is the "only_visible_to_overrides" property changing?