The date, along with others listed on the Ubuntu Wiki and reprinted below, are subject to change at any time. It may be highly unusual that they do, but be aware that the possibility exists.
The most recent version of Ubuntu was 14.04 LTS which was released on April 17, 2014.
- Alpha 1 - June 26th (for flavours)
- Alpha 2 – July 24th (for flavours)
- Feature Freeze — August 21st
- Beta 1 – August 28th (for flavours)
- UI Freeze — September 11th
- Final Beta – September 25th
- Kernel Freeze — October 9th
- Release Candidate – October 16th
- Ubuntu 14.10 – October 23rd
[Source: OMG! Ubuntu!]