Like many we are expecting the Windows 10 Mobile upgrade to start tomorrow, and today we have another carrier source to confirm the rumours.

T-Mobile Croatia support has confirmed that the roll-up will start tomorrow, with users supposed needing to install the Upgrade Advisor app which would enable the upgrade.

Handsets which can expect the update include:

Lumia 435 SS/DS

Lumia 535 SS/DS

Lumia 635 1GB SS

Lumia 640 SS

Lumia 640XL SS

Lumia 735 SS

Lumia 830 SS

Lumia 930 SS

Lumia 1520 SS

Presumably other handsets will receive the update in a wave after this.

Windows 10 Mobile brings a large number of changes to Microsoft’s mobile OS. Read our review of the operating system here.