How to get list of posts to refresh?

That behaviour is down to the caching of the pages on your site and not related to this plugins behaviour itself. It would be beyond the scope of this plugin to start interfering with the caching behaviour of your site.

You might have caching being performed by a plugin (such as W3 Total Cache).
In this instance, after creating a new post, you should always clear or rebuild your cache. Whilst you may have created the new post in the category, the category page inside the cache on which you are displaying your calist hasn’t been updated. Clearing the cache will cause it to be rebuilt when the next visitor hits your website. Ideally, your cache plugin should allow you to clear down a specific page rather than delete every object in the cache even if it has nothing to do with your new post and it’s associated category pages. (W3 Total Cache allows you to do this for example)

Or, you may have set up your site to leverage browser caching (this might even be automatically set up by your web host).
This may be performed by a Page Speed plugin for example to help improve your Google Insights Speed test. Either way, it’s good practice to enable browser caching on your site.
Whilst there are ways of forcing/tricking a visitors browser into loading a new version of an object, you can’t really control the visitors browser without adding extra plugins/controls (i.e. You can’t force the user to perform a cache clear via Control F5 but you can make the browser think an object is new).