There's a higher-level question in here which really comes down to what the institutional policy is. The call anesthesiologist shouldn't be the one who has to arbitrarily decide what's urgent/emergent, what goes, what doesn't, and when.
Our institution has designated from the top down the max number of rooms we can run by 3pm, by 7pm, and overnight. So if I'm on overnight I know that I could potentially be running 1 elective room plus 1-2 trauma/ bonafide emergency rooms if something comes up. Plus we have a list from each surgery subspecialty listing what cases actually count as their urgent and emergent cases. And if there are many elective cases on the board with surgeons who want to operate in that elective room overnight, the trauma surgeon on-call triages the order or asks the individual surgeons to decide amongst themselves if there's a big disagreement. In our system, there's no ambiguity.