Would you really want to risk travel to DUB without a passport ?
AFAIK some airlines will not accept a photo licence as ID for that flight.
Having a passport may not be a legal requirement but one always has to keep airline staff and immigration officials happy.
When I used to fly north/south every week (mainland uk) with EJ I was under the impression that they would accept photo licence ID for internal flights if you were travelling without any baggage.I did used to use my photo licence for those flights but I always had my passport tucked away in a safe pocket 'just in case'
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