>  neither of these items are blocking the merge of this pull request.

That said, looking over the tests in a bit more detail, I see two fixtures here: one for when manipulating sessions is forbidden by the stage of the process the conference has reached (e.g., submission isn't open yet, submissions have closed, etc.), and one for manipulating other people's sessions. With two fixtures, there would be one SUT Factory per fixture, and it would refactor quite nicely. If you have time to do this, I think it would be a useful change.