My concern is that there are likely others who made this switch but were not able to switch back. As I noted, in Yahoo mail you can go back and forth between 3 versions including the beta. Why not allow the same for their calendar especially in light of what I had mentioned? If anyone from Yahoo reads this and wishes to respond, I will publish their response. We all know Yahoo has been having issues as of late and has reduced staff. They should step up here. When I used their service on a more frequent basis, I was satisfied. I note that Google's email service and calendar surpassed them a while back. Their new calendar still does not have quite a few features that Google has but it is improved and I like the interface better than their previous calendar. I hope that Yahoo does the right thing and allows those who use the new Yahoo calendar to revert back to the previous version if they wish.