Water will pool on top of the board and emerge front the lamp holes, could be coming from anywhere above in the cavity.
I've done it to my downstairs neihmghbours due to a dripping cistern overflow- literally a drop every 30 seconds or so but of course it mounts up and then finds a route through.
So whatever it was needs to be found and fixed - but once that's done it should be fine once it's dried out.
Water will pool on top of the board and emerge front the lamp holes, could be coming from anywhere above in the cavity.
I've done it to my downstairs neihmghbours due to a dripping cistern overflow- literally a drop every 30 seconds or so but of course it mounts up and then finds a route through.
So whatever it was needs to be found and fixed - but once that's done it should be fine once it's dried out.