Here are are firmware build details to which can be viewed in the device Settings > About Device.
Sprint Samsung Galaxy S6 SM-G920P
- Android version: 6.0.1 (Marshmallow)
- Android security patch level: June 1, 2016
- Baseband version: G920PVPU3CPF4
- Kernel version: 3.10.61-7280193
- Build number:
- AP: G920PVPU3CPF4
- CP: G920PVPU3CPF4
- CSC: G920PSPT3CPF4
Sprint Samsung Galaxy S6 Edge SM-G925P
- Android version: 6.0.1 (Marshmallow)
- Android security patch level: June 1, 2016
- Baseband version: G925PVPU3CPF4
- Kernel version: 3.10.61-7280193
- Build number: MMB29K.G925PVPU3CPF4
- AP: G925PVPU3CPF4
- CP: G925PVPU3CPF4
- CSC: G925PSPT3CPF4
Main Features:
- Android Security Updates
- Wi-Fi Calling Enhancements
- Bug Fixes
However, the Galaxy S6 Edge+ (SM-G928P) users might also get the same treatment these couple of days.
The update is officially live via Over-The-Air (OTA) and it weighs at approximately 270 MB in file size. The rolling out usually takes into several days, so better check the update manually by going to Settings > About device > Software Update > Check for updates, if you haven’t prompted the availability of the this update yet. You must also ensure that your phone has not been rooted or otherwise the update may fail and you may not successfully get the update.
source: Sprint S6, S6 Edge