Last October, Google announced a redesigned look and feel for Google Calendar on the desktop. Not everybody loves the design (including me, though some people have told me I’m wrong), but soon your opinion won’t matter because Google is about to upgrade your Calendar to the new design anyway.
As the company announced today, G Suite users whose admins chose to be on the Rapid Release schedule will be auto-upgraded started January 8th and those on the Scheduled Release plan will be upgraded starting January 15th. You’ll still be able to opt out of the new UI until February 28th, but after that, “all users will be fully upgraded.”
It’s worth noting that the new design is only one aspect of the refreshed Calendar. It also includes new features for making conference room bookings easier and allows you to apply rich formatting to Calendar invites.