Their search is odd. I used "erase entire calendar" and "erase calendar" and received nothing.
Anyway, Mark also replied with this..same thing you found. Amazing support for a free service!
From Martin at Mobical.....
Go to calendar view, to the right you can choose select view.
Mark my appointments, and in the grey field above Show per page, select all.
Then click on the select all button just above the first appointments check box.
After that just select delete selected.
When a database on mobical.net is empty a slowsync will happen. that means everything on phone will get back to the web. If you don't want that to happen delete every appointment but one.
As for dupes and missing entries..it's weirdly random. One recurring daily item during the week only occurred on tuesday. And I lost my Thursday morning Meeting. And my Bi=weekly tuesday meeting also duped on the 2nd Wednesday... :head scratch:
Later- I deleted all and slow synced and it's all good now. Looks like a few of my long running Tuesday events had end dates in 2008 on a Wednesday. All my fault..Mobical just couldn't digest it
I'm pretty sure these guys are getting my money. The contact sync alone is worth the money for me as a mobile Mac/BIS user