How are excerpts generated?

So if you have the excerpt update feature set to yes, does this plugin rely on the WP cron functionality for updating excerpts if posts are updated? Or do the excerpts get updated at the same time the post is modified? In my testing, it doesn’t seem to update an excerpt when the post is edited unless I manually delete and recreate the excerpt using the plugin admin feature. I’m wondering if I’m just being impatient and the cron process would update the excerpt in a few minutes if I left it alone.

https://ww.wp.xz.cn/plugins/wp-excerpt-generator/