If not booked already, consider moving the DUB-LHR leg to the last flight of the preceding day? Usually there's BA at around 7pm, this should still give the lower fare. Then there are plenty of options to get to Dublin during the day with reasonable wiggle room, and there's an additional benefit that you can check your bags at LHR for the YVR leg and won't have to lug them over to Dublin.

You need to prepare yourself for a shock when you see Dublin airport hotel prices, generally these are not cheap and IHG at the airport is unavailable for a period I believe.

There are lots of questions about DUB just now, so also well worth a scan down the forum. I expect this is about the low tax starts to the US which are great, but the airport issues and hotel prices make it a bit of a devil's cocktail.