One of the big changes between Email Marketing version 4 and 5 is how it uses time. Mailings are now scheduled from your local time zone; if you want something sent out at 3:30 your time, you no longer have to guess the difference between the server's time and your time. You simply schedule your mailing for when you want it delivered in your time, and off it goes.
In doing this new version, we have however discovered that some people's servers are not always configured for their correct time. If you used a web host, relax: you're fine. The chances of such a managed solution having its time incorrectly configured is very low. If you administer your own web server, you should ensure that your computer is properly set for daylight savings time when it is or is not in effect, and that your server's time is accurate and its time zone is appropriate with the time it thinks it's in.
For example, if your server in New York thinks it is 4:30pm but it's on Chicago time, your mailing scheduled for 3:30pm Chicago time could go out an hour late; if that happened, you'd probably be pretty upset. That's why it's important, if you are administering your own server, to ensure that the time on its end is correct.
