Hello,

So my experience of using DUB over the last few years has been that as more US Flights have been added they have added more gates, so they arent US Specific gates.

From memory on my last December trip for example my 09:40am flights to PHL i went through PreClearance around 07:30am which took around 15-20mins. You are then in the gate area downstairs with the rest of the US Bound morning flights downstairs in T2. However my gate was upstairs in T2 and the stairs to those gates were closed and door shut until 08:00. So i presume AerLingus use these gates for European flights in the AM and then switch to US precleared flights after 8:00.

Once it did happen that the airport allowed a small number of passengers through to the "sterile" post preclearance area so all the US Bound aircraft had to be searched and one flight the boarded passengers were taken off for additional security checks.