שֵׁשׁ-מֵאוֹת אֶלֶף רַגְלִי, הָעָם

Here is the formulation of the 600,000 Pasuk, which we restored to its original position

וַיֹּאמֶר, מֹשֶׁה, שֵׁשׁ-מֵאוֹת אֶלֶף רַגְלִי, הָעָם אֲשֶׁר אָנֹכִי בְּקִרְבּוֹ

It "replaces" the phrase

כְּשֵׁשׁ-מֵאוֹת אֶלֶף רַגְלִי הַגְּבָרִים, לְבַד מִטָּף

which, in my understanding, P borrowed from the original Pasuk, and added to the first Pasuk here. There is an important difference between the two formulations. The original Pasuk has that the nation started out as 600,000 people; the copy version has 600,000 men, excluding women, and excluding children. We take it that the change is indicative of an agenda.