I do not know the answer to your question but wanted to suggest if you haven't already to download the desktop wallet https://signatum.io/#downloads.  It's less than 1GB total to sync.  Then change your auto-payout address to your desktop wallet.  I'm not sure when Cryptopia added this text to their wallet on their account page but it says on mine "WARNING! Please do not mine directly to your Cryptopia addresses, We do not support generated transactions from pools like P2Pool etc." 

In general you shouldn't mine directly to an exchange.  There's no reason to with the SIGT especially wallet being small and tidy right now.  I hope someone can help you with your question about your coins.