I made a sponge cake with a jam filling. After crum coat I found that there was a pool of syrup/ water that lad leaked out and thought nothing of it. Did outside layer went to decorate and the side has just fallen apart. It’s for a client this afternoon what do I do? 

I’m so sorry no one could give you any help :(   Hope you were able to fix it ok   Personally I would have glued it together with b’cream & hope it stayed 

I guess I am too late, but the only thing I can think of to try would be scraping off the loosened buttercream, drying the sides of the cake as much as possible, making a dam of stiff buttercream or ganache and try to seal in the filling, then refrost with buttercream.  As kakeladi said, hope for the best.

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