You can make some changes to a published tour, but some require you to unpublish the tour and then republish it.
If you need to make any changes to the constellation, you can go back into "Build tour," make your changes, and then simply click Publish again. You do not have to unpublish the tour. If you need to remove a panorama from your tour entirely, simply navigate to "Build tour," remove the panorama from the constellation and click Publish.
If you need to make edits, such as adding your nadir or blurring any images, you must unpublish the tour. These changes are appended directly to the images, so you must remove the tour to make these changes.