Solved
How to turn off Shield Wall (or other sustained abilities) in Tactical Mode?
It sucks that there's no indicator that a body is required when drafting a question on mobile.
I forgot to post here after figuring out what to do and posting on reddit. "Turning off a sustained ability is treated like ordering a new action. Time must move forward in order for the ability's icon to update, which is counterintuitive to me since I expected the icon color to immediately toggle when I try to turn the ability off."
