After you publish an annotation in Rx Bricks, the students at your institution will be able to see it immediately. If there is material that you want to withhold—perhaps a video or an annotation on a complicated topic that you don't want your students to get mired in too early—you can easily unpublished it.
By clicking the vertical dots in the upper righthand corner of the annotation, you can choose to detach/move, unpublish, or delete the annotation.
When you unpublish it, you are moving the annotation back to a draft stage, which means that your students won't be able to view it. You may find that you want to unpublish an annotation that requires more research (for example, "Hmmm, perhaps I should double-check the wording of this limerick before I share it with students") or have one of your peers look at it first. Either way, the annotation will remain in place and can be published at any point once you're ready to share it again.
When you delete an annotation, you are making the decision to permanently remove the annotation from the brick. After making this decision, there is no turning back. The annotation will not be retrievable.