Multiple chats sessions with same contact in S4B window ?

I have a few questions for those who are experiencing problem with what I'll call "split conversations."  If you can help me, I would appreciate it.

• Which version of the app are you using?  This thread started in January, but we made significant improvements to split conversations in the April release (16.6).  If you are using an older version of the app, updating could fix this problem.

If you are still seeing the problem:

• How frequently does it happen?
• Have you noticed a pattern when it happens?  Are there steps that reliably cause this to happen?  If so, please describe in detail.
• Does a conversation get split when there are messages sent close to each other (within a minute or two) or over longer periods of time (>10 minutes)? 
• Does this tend to happen with specific contacts or in general?  When it happens, are the people you are IMing with also on Mac or Windows or mobile apps?

Thanks,

Phil Garding (Microsoft)