I will vote for South. B is better but South is a good trade off in terms of location and comfort. It's 6 minutes walk from there to the usual domestic gates, so you can stay then until 30 minutes before departure assuming it is the usual domestic gates (though sometimes they use gates by South).

If you do go North, which is 2 minutes from the usual domestic gates, just go away from the main drag, the outlying sections or the terrace can be quieter.

Note that bacon rolls stop being served at 09:30 hrs, but the other breakfast items such as porridge and continental breakfast will go on after that until about 11:45 hrs.