I'm having issues posting and editing my Company Updates across several of my profiles.
When you post a company update, next to the Post button there is a Post to drop-down menu where you can select or unselect profiles to post to. After you post, navigate to one of the profiles you posted to (using the Master LEP toggle at the top of the Employer Center) to see your preview. If you end up on a page that you did not post to, it will appear like your post did not work.
When you bulk post to multiple profiles, once the post is live a separate update for each profile is created. If you want to edit or delete the post you will have to individually edit every post for every profile.