Error connecting to upgrade server

[dmsergeevN26]

Trying to run the upgrade from the UI on Openwrt19.07 and getting the following:

Could not reach API at "https://sysupgrade.openwrt.org". Please try again later.
TypeError: response.latest is undefined

I see it's trying to make a GET request to https://sysupgrade.openwrt.org/json/latest.json which returns 404.

[efahl]

This is due to one of the many changes that have been made to both the ASU server and LuCI app in the past six years. You won't be able to use the LuCI app for upgrades on that device, as it has not been supported since April 2022. Your best bet is to use the Firmware Selector, https://firmware-selector.openwrt.org