If you are referring to the STATUS of the Q EV output, then this means that
the server contacted the client, the backup started, but never completed.
This could be due to a network problem, the client server going down, or
it's still running. Somewhere in the 4.1 maintenance Tivoli added this '?'
status for events that have started, but haven't received any completion
response from the client node.  Further APARS I saw stated that actual
descriptions were to be added instead of the generic '?'.

Check the activity log for around the time the schedule started for that
node to see if you have any errors. Like 'connection with client severed',
or idle timeouts... Also, the status of '?' is NOT listed in a QUERY EVENT
output with EX=YES.

Bill Boyer
DSS, Inc.