The online preview – available from the default form and also by clicking on your newsletter, then clicking the “I Want To” button, then selecting “Troubleshoot” from the drop down menu, then selecting “Diagnose” on the following page- shows the top (most recent) articles in the newsletter’s article feed.
It does NOT show either (1) What was mailed most recently, or (2) What will be mailed in the next mailing.
A preview will typically show the most recent 5 articles, the next mailing may only include the top one because that’s the one that qualifies. The contents of each mailing are determined by the schedule you set for your mailings. You have the option to change the amount of articles in a preview, however the default is set to 5.
For example, say you post daily and are on the default overnight delivery schedule. The preview will show the last 5 entries, but the overnight mailing will only take today’s entries – which will be just the one dated today in this example.
If you want total control over your mailings and what is sent when, change the schedule to be manual / on demand. Steps on how to accomplish this can be found at the following link: