EI330
Should be built and operational before end of summer. Would be surprised if regional ops don't move there for most of the day and of course morning/late evening ops.
Chances are most short haul at 300 gates for EI will end as they will handle some wide body arrivals before first departures start. The shuttle bus will not be flight specific and just operate in a loop while flights are scheduled from there.
An enhanced T2 transit facility will also be built and it will remove the Dublin Airport security screening for transit passengers if your departure airport is a US/EU one that have same standards as DUB.
The set up will be like AMS and cut transit times even more.