After updating Lightning an BirdieSync the following problem appeared:
as there is no field for birthdy-dates in Thunderbird's contacts (I know now that there is a possibility to get one, I didn't know that then), all birthdays were entered as recurrent events. After the first post-update sync, all birthdays were doubled on the desktop (not on the handheld). Every other event is okay, but the annual recurrent events are now two times on that specific day.
I tried to delete one of the two - after the next sync it was still only one event on the desktop but now two ohn the phone

Also strange: wenn trying to edit a birthday in lightning, I get to choose between "only this event/all events of the series" (or something like that... got it in German here). But in the settings of that event, there is "repetition: never", just as if it was a singular event.
I hope I made the problem clear an I'd be grateful for any help

Cheers
Carter