Samsung is rolling out an OTA update with the March Security Patch on Galaxy Note 4 on Sprint Network. The update is rolling out with the software build number N910PVPS4DQC1. The update weighs 333 MB in size which includes March Android Security Patch. In this regular bug fixes and other improvements as well.
It is an OTA update so it might take some time to reach each and every user of the Samsung Galaxy S6 Edge+ to get the update. Meanwhile you can also check for the update by going through the Settings>>About Phone>>Software update.
We Recommends you to ensure that your phone is at least 50 percent charged and connected to a WiFi network to avoid extra data charges.