Tiled roof? I had a few tiles displace in the rough weather a month or two ago. Didn't notice until water started pooling on the plasterboard ceiling and dripping through the downlight and down the back of the cornice.
I managed to knock the tiles back into place enough to limit the water ingress a bit. Didn't lose the ceiling. Sometimes it's better to punch a hole in the ceiling with a screwdriver or something to give the water an outlet rather than have it collapse. Hope they don't have blow in insulation or it'll be a mess.