With Desktop Manager 4.7 installed with the BlackBerry Automatic Update option selected, and an Internet Connection when you run Desktop Manager, it will automatically detect your device's OS, and offer to download and install the update if available.
You can get it here:
https://www.blackberry.com/Downloads...93E4F3BB068C22
I STRONGLY recommend getting "Desktop Manager 4.7.0 B50 English - Without Media Manager":
https://www.blackberry.com/Downloads...2B05298837C8B5