Assume that a Lync 2010 client receives many presence change notifications within a short time frame. For example, you join a conference that has many participants who keep changing their presence. In this situation, the presence of certain contacts may be displayed as Updating….
This issue occurs because of a throttling limit on BENOTIFY messages.
To resolve this issue, install the following cumulative update:
2884632 Description of the cumulative update package for Lync 2010: October 2013