One of the strange things about the Academy Awards is how arbitrary qualification for the supporting acting awards is. The supporting acting categories were created in 1936. The rules of eligibility have evolved over time, but the bottom line is that there is no bottom line about what constitutes a lead performance and what constitutes a supporting performance. The decision is made by the studio, which decides on its own which category it wants to submit to and campaign for.
This can lead to oddities, like Frances McDormand going lead for Fargo (1996) with 28 minutes of screen time, while William H. Macy went supporting with 32. But McDormand dominates memory of the film, so maybe it makes sense. On the other hand, some performances seem even too short for supporting. Beatrice Straight won supporting for Network (1976), for less than six minutes of screen time. But it was a brilliant performance, and that’s what counts.
Anyway, this year in particular, there seems to be more than the usual amount of unpredictability about who goes where. Oscar prognosticators are stuck until the respective studios make some decisions. Here’s a brief rundown: