When can i expect wp10 update on my uk tesco lumia 640?

[voodoocars]

As above. I dont want to install the preview in case it doesnt work correctly, unless anyone has evidence to the contrary.

 

[Ed Boland]

The official Windows 10 mobile update won't be available until October at the very earliest. With that said, many of us here are running the latest Insider Preview (build 10512) on our phones without issue.

 

[Pete]

There's no reason why you can't install the preview and see how it works for you. One person's idea of "great" may not be the same as yours.

Microsoft has a tool that allows you to revert back to Windows Phone 8.1 in a very hassle-free manner.