The update is live on the Unlimited server and will be required to join. The launcher should automatically prompt you to update if you have Unlimited installed. If you don't have unlimited installed, feel free to grab it here.
After a brief hiatus, Serendipity Network will be reopening on Sunday June 21st at 12pm ET. We'll be offering fresh servers on FTB Infinity and Serendipity Unlimited 7, which will be available on the Technic launcher shortly. We hope to welcome everyone back soon!