grp.update function

[gtsamis]

Just notice some strange behavior on my LM3 and heavy load on BUS. It turns out that function grp.update send telegram to bus although it shouldn't.
I am not sure if that happened on new firmware (20150917) or it was working like that before. 
Can someone else please check if there is actually a problem with grp.update?

I am attaching a screen shot from group monitor capturing a grp.update on some dummy address used only for visualization.