Does it ever happen that after posting you spot some mistakes in your text? With Projectcampus you can edit your text after posting. Click the lines in the upper right corner of the post box and choose 'Edit item' from the dropdown menu. With this option, you can edit the text, but also change the attachments you uploaded with the post.
You can see an item has been edited by the 'Edited' note on the post. You can click it to see the editing history.
Note, however, that when you substantially change the content or the attachment to a post, it is convenient to add this to the post, mentioning for example the changing date and what has been changed.