The Samsung Galaxy Note 4 on Verizon has been patched with an update for Blueborne, the security vulnerability that was recently discovered and patched in updates that were sent out to devices like the Google Pixel and Nexus phones. This is more than likely the update that will introduce the September security patch to this device albeit Verizon doesn't state this. That said, anyone still using the Galaxy Note 4 will still be better off after downloading this update since it patches the Blueborne Vulnerability.
Verizon's support page for the software update doesn't mention how big the update file is, but as is always the case it's recommended that users have close to a full battery or at least 50 percent battery life left before beginning the update. Verizon's page also notes that users will need to be connected to Wi-Fi or have a strong connection to the cellular network before starting the download. The battery life is certainly a more important factor, as you could do a fair amount of damage to the device if the update starts but then the phone dies in the middle of the process, as this could likely result in bricking the phone.
Verizon also mentions that the software update should take about six to ten minutes to complete the entire process. Once done, users with the Galaxy Note 4 should be on build number MMB29M.N910VVRS2CQE1 for the software version. Since this may be the September security patch update, users can expect the device to have all of the security fixes that were included with that patch in addition to the Blueborne fix, though keep in mind that this may just be a patch update to fix Blueborne and come with the August Security patch. The update should be on its way out to users as of now though it's also possible that not all remaining Galaxy Note 4 owners on Verizon's network will have the update available for download. If the alert hasn't come through, users can always check for the update manually by navigating to the settings menu, opening up the About Phone section, and then tapping on software updates to see if it can be installed.