It seems from my own experiences and other community posts (e.g. https://community.alteryx.com/t5/Alteryx-Server-Discussions/Scheduled-worklfow-not-picking-up-the-qu...) that when scheduling a workflow in the gallery, the gallery will run whatever version was most recently uploaded, regardless of which one has been labeled as "Published". Since naturally the intent is for the Published workflow to be the only version running, it would be nice (adnd would me much more logical and intuitive) for the scheduler to run that version.