Incorrectly showing – Last modified date Vs published date for new articles

Hello, Its nice plugin. It is correctly working for old posts where I am showing last modified date replacing the publishing date. However for new articles if I schedule with future date, it shows modified date < schedule date. e.g. If I update the article on 5th October and scheduled for 10th October. On 10th October, the date shows as 5th October. But I published the article on 10th.

How can i show published date only where last modified date < published date?

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