On 25th March Microsoft commenced upgrades for Windows Phone 8.1 devices to Windows 10 Mobile.
Customers can install the Windows 10 Upgrade Advisor app on their phones to check if it is eligible for upgrades.
What is the Windows 10 Upgrade Advisor app?
The Windows 10 Upgrade Advisor app will tell you if your Windows Phone 8.1 device is eligible for the upgrade to Windows 10 Mobile. If you are eligible, it can also help free up space on your device so you're ready for the upgrade.
How to install the app
1. On Windows Phones, at Start, swipe over to the All apps list, and then select Store.
2. Search for the windows 10 Upgrade Advisor app, and then install it on the device.
3. Open the app on the device. It checks your device and lets you know if it’s ready for the
upgrade, if an update is required before you can get the upgrade, or if your device can’t be upgraded.
Confirmed devices purchased from Optus which are eligible to receive the Windows 10 Update:
Lumia 930, 640, 640XL, 830, 532, 635 (1GB), 636
For more information on this upgrade process you can find out more through Microsoft: