This post over at the DayZ forum makes sense.
I used to have the same problem when I logged out.
I worked out it was because I didn't wait for the Hive update communication (as Detta mentioned).
Since the "not saved" time thingy was removed from the Debug Monitor I had forgot all about it.
So now you need to do this:
Press "P" and click on your name, look at the numbers on right "Ping" and Bandwidth".
When they change you are good to go.
I always wait for them to change at least twice just in case.
Never had a problem since.
Hope this helps.