You can create, change and save your Biteable video as often as you need to, here's how:
After you've made changes to your video, head to the Publish tab and you'll see a message on your screen that says 'Changes have been made to this project, click below to update your video'.
From there, you can click the 'Update Video' button either over your video or below it.
Once your video is finished updating, the changes will be saved and applied anywhere this video exists. In other words, if you have shared this link previously or posted it to a website, that link will now be updated with the most recent video changes.