I have a similar issue to this question. I managed to fetch ugcPosts from a test company but not filter them by date with the API, I had to do it programmatically. I see we can sort posts either by created or last modified time.

Now I am trying to fetch the comments, but I noticed that if I create a comment on an older post, the related activity is not updated, meaning that I cannot sort it in any way to see if that post got new comments.

Is there any way to sort the posts by "update" or something similar? If I add a new comment on an old post, I still need to fetch that post and check if it has any new comments, which seems off. The "Last modified" sort applies only to a post that has been edited...