Tabs in tab set have disappeared

Yesterday I spent several hours on my development site setting up a set of tabs and got them all working just the way I needed them to work. Today, I went back to copy them over to my staging site, hoping to get them live by the end of the day, and when I went to edit the tab set, the content for all the tabs was gone. There are no tabs showing on the page any longer. What happened to them? Can they be recovered? This is a huge problem for me, as I am on a deadline and now have to recreate all the work I did yesterday and hope that it doesn’t disappear overnight again. We were considering upgrading to the PRO version, but this has me thinking twice about that.