DS-156 alterations

[Rbshiv]

My parents have an interview next week.
DS-156 which I sent to my parents is signed by me, since I am the one who filled the form. But the mistake is, I haven't taken the print out back-to-back. So, can I retreive the same form that I have filled and change the 40th column (application prepared by) ??
Can I put my parents name instead of mine in the 40th column? So that I need not have to sign and mail the original signed document. I really don't have enough time to do it.
Please help.

[s_r]

Hi,

I filled the application for my mom, since i am in US and couldn't send my signed form to my mom before her interview date, i went and updated D-156 with my sister's name and save it as pdf, asked her to take a printout in India and sign it. she did the same and my mom didn't have any issues.
hope this helps