I think it's bad news...
My understanding is that night VFR is only permitted within a control zone, so unless you can reach the Cork zone boundary before night then you'll be IFR on your x-country section.
Night in Ireland:
Summer (1/4 to 30/9) - SS+30 mins
Winter - night starts at sunset.
(I definitely second CSX's comment about VMC around Cork in November.....wouldn't want to have anything too urgent to get back for)
