We had an unexpected problem with one of our servers yesterday and it resulted in missing calendar entries in some user accounts. The problem is fixed now and everything is back up and running.
I was unable to communicate this right away as I was traveling for a business meeting. The delay in communication was primarily unfortunate timing. Once I was off the plane and back on my seat we were able to troubleshoot the problem within a couple of hours.
Please accept our sincere apologies for the inconvenience some of you faced and also for the suspense and wait you went through.