Hi,

You can refile a T2 from TurboTax business inc. Search for the form T2 ADJ. Then:

1) Make the required change ( add info on schedule 4 for example)
2) Complete the T2 Adj: mark return as amended and give a brief explanation as to changes in the return.

Then file as usual. 
Hope this helps. If you need further assistance use the live chat feature in TurboTax business. A Turbotax Expert can help you