If you need to update a video, audio, image, or PDF file in Google Drive - but you want to maintain the same link for the file because you've already sent it out, just right click on the file in your Google Drive and choose "Manage versions" from the list.
Now you have several options. You can see all the versions of your file as well as a button to upload a new file. If you click on the three dots menu for each version, you have the ability to delete, download, or keep forever. Generally, versions older than 30 days will delete automatically. If you want to keep an old version for some reason, be sure to go in and tell it to 'keep forever'.
Now you can upload a new version of your file, or even a brand new file if you wanted, and keep the same URL link. This can come in very handy if you noticed a mistake in a file you have already shared out, or if you need to update your file with new or updated information.