Not much you can do about this. There will be few chances to spray according to met eireann. But do watch out for it and at the first signs of browning on the underside and edges of leaves cut off the foliage and burn it. Don't add it to your compost heap as it can be passed on into next years beds through the compost. If the blight is prevented from travelling down the stalk and into the spuds they should be perfect when you dig them out.