If you look on U2.com it says:
Recently announced 2nd shows: Los Angeles (May 21st), Chicago (June 4th), East Rutherford (June 29th), London (July 9), Rome (July 16), Paris (July 26) and Amsterdam (July 30).
Wednesday, 18 Jan., 9am - Presales open for 'Red Hill Group' (longtime subscribers)
Thursday, 19 Jan., 9am - Presales open for 'Wires Group' (new subscribers)
Friday, 20 Jan., 5pm - Presales end
Monday, 23 Jan. - Public on sale London (July 9), Rome (July 16), Paris (July 26), Amsterdam (July 30)
So long time gets priority, then the rest, just like the first round... Ok.