Okay, the 'spontaneous' mission end/roll over is now fixed, it was due to me leaving the setting 'Team points per round' at 0 (zero). So, have changed this to value of 1410065407.
Next point of attention will be registering the server correctly, so it will be using a Username to logon...
Well, somehow I got it to rotate the mission after it's been running for two hours now.
Mind you, it runs for two hours if nobody is using it, so nobody gets killed, nobody bails out... So at least we won't be caught at night around there anymore!