Yes:
This was stated in the release post at the very top:
- If you are already on 1.1, 1.1.1, or 1.1.2, you MUST do a full ‘reflash’ of the SD card to 1.2.1 (this involves removing the sd card and flashing via a computer. More details here: How to reflash the operating system on the Onefinity (Full SD card image)
Full SD Image