After you file

Right,  and since you stated the reason is because of a bankruptcy so I will assume that one spouse wants to limit their liability which it the very reason that the tax law does not allow to change to separate returns after the April 15 due date - once a joint return is filed and the due date passed then  both spouses are equally liable for everything on the tax return and they cannot remove that liability after the due date by amending.

**Disclaimer: This post is for discussion purposes only and is NOT tax advice. The author takes no responsibility for the accuracy of any information in this post.**