unlimited sitemap generator old links

[fpscherer]

I have seen that the Unlimited Sitemap Generator is keeping old links even if a new crawl did take place. So my question is: Is it necessary if doing some changes in case of links to delete the files the sitemap generator did create before in the root directory, where the created sitemaps reside to get rid of old links.
So: does the sitemap generator just adds new found links in the way an incremental scan would do or is it a wrong configuration in my case that those sitemaps just receive an incremental actualization?
Or is it necessary to delete those sitemap files before new crawl occurs?

[XML-Sitemaps Support]

Hello,

make sure that non-existing pages URLs return 404 http code (which means "file not found" to make sure that the pages will not be indexed)