Awareness of this need came out of reviewing patrolling workflows with @Risker. A user with the oversighter role needs to be able to perform reverts on any object they are patrolling so that they can remove offending content from a record before suppressing the edit which introduced the offending content.
In Django backend terms, this means that members of the Oversighter group need to be granted the "toolinfo.change_tool" permission. This will translate to a {subject: toolinfo/tool, action: change} permission in the CASL frontend rules.