Beyond updated to 1.6.1
Server was updated to the latest recommended version, update your client! Thanks to FTB for not considering it necessary to include a changelog for the last 2 version, this update was a bit delayed. Anyway you can find an unofficial changelog below.
1.6.0 - 1.6.1 https://www.feed-the-beast.com/projects/ftb-beyond/files/2418191