I got 2 RedZone tickets for Dublin at 9am on Wed. No issues. Logged in to U2.com, tours page - link to tickets for Dublin. 8:55. The timer ran down 5 mins, refreshed at 9am, and I got 2 RedZone tickets straight away.
Did not need my pre-sale code, although I'm pretty sure they will count against my pre-sale amount.
Cannot Wait!!