Initially I hoped this meant there was another update (enhancement) on its way for the General Register Office's Civil Registration Indexes, but I think this is unlikely because a note posted on the online front door of the Department of Arts, Heritage and the Gaeltacht (which runs the site)
says the entire DAHG site is down for maintenance.
I've tweeted the Department to find out how long they expect the downtime to last.
UPDATE: And in a trice, the site was restored! I'd love to think it was my tweet that prompted such speedy resolution, but I suspect it wasn't! There are no obvious updates that I can see.