Mr. Chair, you can't challenge the chair if it's not officially a ruling of the chair. You didn't make any decisions; you just said there was a list. Until you recognize Mr. Duncan, no decision will have been made by the chair.
We can't challenge the chair, otherwise we're going to challenge each of the notes you take, Mr. Chair. That's not how it works. A decision will have been made when you recognize Mr. Duncan. At that point, Mr. Turnbull can say that he was next on the list. At this point, all you have done is indicate the names that were on the list, but you have not made any decisions. These are notes that you made, not a ruling. You named the people who were on your list. Are they going to start challenging every single note you make?
You have not yet made a decision to recognize Mr. Duncan or Mr. Turnbull.