Thread datawriter functions running twice on xf 1.5


I am working on an addon in which i have to perform some functionality after thread creation. So I am extending "XenForo_DataWriter_Discussion_Thread" for that and using the method "_postSaveAfterTransaction()" but it keeps running twice every time.

I though there may be an addon issue but i tried this on fresh installation of xf1.5 and facing the same issue. Although it works fine on xf1.4 series.

Anybody facing the same issue ?