Importing Older Comments

Thanks for this great plugin. I have already used it on a new website. But right now I am trying to figure out how to use it on an existing site with more than 300 posts and 1000+ comments. On the Settings – Discussion page there is a check box that says Copy post comments to new topics (when available). But it seems to me that after checking the box I still need to go to each post and republish it in order to create topics for posts and import comments as replies. Is there a better way to do this?

Thanks

https://www.ads-software.com/plugins/bbpress-post-topics/