how video continuous in Replace With After Effects Composition?

I want to roto brush my subject, the one who is speaking, for example. roto brush is only done in After Effects. Here, we need to create an adjustment and Replace With After Effects Composition.

The problem when we go to After Effects to roto brush the subject is that the video must precisely follow the Premiere video. But it's empty inside After Effects. Is there a way to have the continuation of the clip inside it? Otherwise, I have to exactly find that moment's second, throw the original clip into After Effects, and cut it from there. I thought maybe there's an easier way.