May be some time in the future, yes.  But as it stands, I'm afraid the answer is no.  This feature is currently available only to e-filed returns.  And you can't relock an unlocked return.

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The program will automatically lock the return after you e-file the main form. Extensions and paper filed returns can't be locked at this time.

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https://proconnect.intuit.com/community/electronic-filing/help/how-to-lock-and-unlock-returns-in-pro...

Edit: You can't relock an unlocked return per se.  But you did have an option to create a locked copy of the return when you unlocked it; if you didn't use that option, your return is forever unlocked - probably until you use it to file an amended return.