How can I upgrade lumia 940 from windows 8 to widows 8.1?

[Windows Central Question]

Once before, I got an update but ignored it not knowing what it is about. I got several updates but kept ignoring them. Now I want to upgrade my lumia 920 from windows 8 to windows 8.1 version. It is currently Amber. How do I upgrade it? Should I wait for an update which seems unlikely to come since it was introduced way back in 2014? Will i never get the update message again?

 

[Dusan Randj]

I don't see point in this question. Just go in settings, phone updates and check gor update. It shall be forever available.

 

[Czesky]

If not, download Windows Phone Recorvery Tool and then update.