That tag is archaic and of no use.

https://webmasters.googleblog.com/2007/12/answering-more-popular-picks-meta-tags.html [webmasters.googleblog.com]:

Occasionally webmasters needlessly include "revisit-after" to encourage a search engine's crawl schedule, however this meta tag is largely ignored. If you want to give search engines information about changes in your pages, use and submit an XML sitemap. In this file you can specify the last-modified date and the change-frequency of the URLs on your site.

Ok so that revisit-after is ignored. Thanks! however you said "change-frequency" of url. Most of my pages are one shot news articles so they are never changed.

However there are certain pages where news articles are added (like pagination etc). So i need to adjust the change-frequency of these URLs in the sitemap then? Thanks!

https://webmasters.googleblog.com/2014/10/best-practices-for-xml-sitemaps-rssatom.html [webmasters.googleblog.com]:

Specify a last modification time for each URL in an XML sitemap and RSS/Atom feed. The last modification time should be the last time the content of the page changed meaningfully. If a change is meant to be visible in the search results, then the last modification time should be the time of this change.

XML tag definitions:
https://www.sitemaps.org/protocol.html#xmlTagDefinitions

But one can't keep changing the timestamp of change of a url after submitting the sitemap to google search console? Sorry I'm confused now

Search engines decide for themselves how often it's appropriate to re-crawl. It's a combination of two basic factors: how popular a given page is, and how often its content changes. If the page only gets ten visits a day, it doesn't matter that content changes every five minutes. Conversely, a page that gets millions of daily visits will get crawled several times a day even if the content hardly ever changes.

The present page--like all Forums threads--doesn't have a "revisit-after" meta, but you can bet Google will recrawl it within the next 24 hours.

The WW pages are reindexed almost every hour because, as lucy24 said, they get high and constant traffic.

I've actually seen my own typos indexed while searching for additional info to help someone with. Then I rush back and fix it :)

Ok great guys as always thanks! I'll make no changes then..