How long to keep moulddr dragon

Hi all,

Thank you to everyone who gave me advice about making my dragon. I have decided to make it out of Krispie treats, then cover with a layer of chocolate to smooth out, then cover with fondant icing and paint over parts of it with metallic dusting. The cake is needed for 5th May, so 3 1/2 months away, but I want to have a go at making the dragon now as I am uncertain how artistic I can be. My question is this: If I make the dragon now, can I store it in an airtight container for 14 weeks and would it still look good or do you think it will deteriorate too much? The dragon is just for decoration and will not be eaten but needs to look good :0)

Many thanks, Alison