Broker: Legion Assaults
Legion assault Data Broker plugin, shows countdown to next event.
Note
So this works fine but only for eu by default, If you want you can change value for 4th line (TStart variable) something that is right for your time using this list.
Usage
This is data broker addon to use it you need LDB display addon (Statblock, Titan Panel..)
Then just export zip from Downloads to Wow\Interface\AddOns.