Please upgrade your Yún - latest is 1.5.3

Why does https://www.arduino.cc/en/Main/Software show a Yun Image for 1.5.3 which according to their change page (GitHub - arduino/openwrt-yun: A custom version of OpenWrt, targeted to the Arduino Yún) was last updated in 2014?

I thought OpenWRT was supported better and updated more frequently than Linino but Linino's latest version is from 2015.

Is OpenWRT Yun still supported?