Is here wordpress plugin to renew or republish a page? (Rank factor?)

What i see on my competitor: He have an old site with the same content for years, but if i'm searching in google with "past 24 hours" his page is there, with ex: 5 hours ago.... But, page is the same, no change omn it. I know that can be a script. ( He is ranking 1 with this ). ( I think this is a rank factor, observed now on 2 websites from 1 spot) (non english websites)
Question:
1. How see Google this, fresh content? if content is the same just pages are updated, republished?
2. Is any wordpress plugin to can do that?

Thank you.

Nobody? Do you see similar situations? Thank in advance.

I doubt a plugin can do that. You need to force Google to index and re-index your page somehow... I can not imagine such a tool. Alas!