It's not always easy to see, but there is a toggle in the view so that you can find your saved drafts.
If you save a post to finish later, you may need to change the display from view published only, so that you can retrieve and modify your draft.
To access your drafts, return to the forum page and set it to List View. Under Display - choose the action item drop-down arrow
and select Drafts Only or Show All to view the saved post. Select the draft's title to open the Thread page. While viewing your post, point to it to view the functions for Edit and Delete. Select Edit to open the content editor. After you make your updates, select Save Draft again to update the draft or Submit to publish the post.