Last usage user ID missing in TMX Export?

Hi there, I came across a glitch in the TMX export - i.e., the Last usage user ID is not exported to the TMX file and as a result, the last usage user ID is reset to the CreationID when the TMX is imported into a fresh TM.

Is that a known issue? Using Studio 2015 latest patch level...

To repro, try the following:

Import a TMX file into a fresh TM.
Use this freshly imported TM to translate one segment in a document (make sure the segment is indeed contained in the TMX)
Confirm the 100% match that you will get.
Click into the previous segment and back into the translated segment.
OBSERVE: The Last used by field in the TM match now shows your user ID

Export the TM to TMX - you will see something simliar to this in the TMX for the TU that you confirmed in the step above:
<tu creationdate="20080406T213648Z" creationid="DANIEL" changedate="20090602T162108Z" changeid="FREDDY" lastusagedate="20151102T111428Z" usagecount="2">
OBSERVE: The lastusagedate field shows the date and time when you confirmed the segment in the editor, however, the lastusageID field is missing.

Reimport this TMX into a freshly created TM.
OBSERVE: The lastusedID is filled with the creationID (visible in the Translation Memories view in Studio).

Any ideas why is this the case and will something like this get fixed in a future build?
Many thanks, Tom