While Irish airspace remains open, UK airspace has closed due to the ash cloud, with flightsd from Derry affected. Here is the most recent statement from City of Derry Airport -
The volcanic ash cloud in UK airspace has caused disruption to a number of flights operating to / from City of Derry Airport
The following flights have been diverted / cancelled:
Flight No. Route
FR9884 Liverpool – City of Derry – Diverted to Belfast City
FR9885 City of Derry – Liverpool - Cancelled
FR611 London Stansted – City of Derry – Diverted to Belfast International
FR612 City of Derry – London Stansted - Cancelled
RE287 Dublin – City of Derry - Cancelled
RE288 City of Derry – Dublin - Cancelled