Built out the new newsletter cards, show the scheduled, draft and published newsletters as different lists.
Filter by newsletter so you can see the emails for each newsletter.
Added in support to edit a scheduled or draft email.
Schedule or update the schedule of a newsletter.
Each step allows for previews to be sent.
Next step is to nail down the flow from screen to screen, create a newsletter, followed into the create email, then schedule screen. A user will be able to bail out at any stage and the email will be at the stage it was at when you exit.