ATL-DUB and JFK-DUB on the 12th are both so/so for availability - I would go thru ATL simply because of the ATC delays that occur in the NYC area, unless you take the redeye to JFK on the 11th you only have 2 flts that will connect JFK-DUB, but thru ATL you have more flt options LAX-ATL that will connect to the DUB flight..