This affects some, but not all recurring tasks. I don't know what determines which ones it affects.
For me, this is a problem because I use the deadline to show me when a task begins to be relevant. So these changes happening on their own makes me miss important tasks.
I use producteev on the web and on android.
Just to clarify what's in the screenshot, the deadline was changed from 2014 to 2015 because this task is set to re-occur yearly. The problem is that I never checked it off as done, and it moved anyway.
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