When you add a new event in a series all followers of the previous event are automatically transferred to the community of the new event. To invite these followers and let them know about the new event, you can you use the Group message option.
1. In the Manage event area, click 'Community' and 'Messages'.
2. Then click 'Group messages', and choose the "Followers not attending" as recipients.
3. Write your message, and include the link to your website registration page to promote ticket sales or to your event website overview to create awareness.
4. Send immediately or schedule a time for the message to be sent.