In Absorb LMS, Amazon S3 is utilized for file storage of content added to portals via the File Manager or otherwise. Any time a file is uploaded, replacing another file of the same name, the file it is replacing can be cached for up to 24 hours. This can translate to replacement files not appearing for learners immediately after upload. Depending on your organization's needs, it may be preferable to replace content with files that have a suffix added to the original file name.
For example, if you have a file called request-form.pdf, you may want to upload the same file with a variation on the file name like request-form_v2.pdf. This will avoid the previous file being cached, and allow users to see the new file immediately. It is also recommended that the previous file is deleted to avoid any confusion, aid in troubleshooting, as well as reduce space used.