Wirelessly posted (Blackberry 8700: BlackBerry8700/4.2.1 Profile/MIDP-2.0 Configuration/CLDC-1.1 VendorID/120)
OK - will stick to South in future!
It is somewhat inconvenient though if you arrive with the HEX and then leave from A4 like I did today.
The lounge is also more convenient at North than at South.
One problem is that you can't see the queues from outside...