The countdown clock will start at 00:00 GMT (Pacific time) on Monday 26 April 2018 and will run for 7 days, ending on 28 April 2018.
The countdown will be accompanied by an interactive countdown timer and by a series of live audio alerts, including the following: 1.
The first live audio alert will be issued at 00.00 GMT on Thursday 27 April 2018 with the countdown timer starting at 00 hours.2.
An interactive countdown will begin at 01.00GMT and will be preceded by the announcement of a new time and a countdown clock at 02.00 and 04.00, respectively.3.
The live audio will continue for the next seven days with the clock starting at 06.00UTC and the countdown going up every hour.4.
A countdown timer will start every hour until 08.00 hours on Thursday 28 April.
The timer will then go down every hour from 08.01 to 07.00.5.
A timer will be displayed at 07.15 hours with the next countdown timer going up at 07,30.6.
At 08.15, the countdown will end at 07:00 hours and the next timer will begin.7.
At 09.00 the countdown begins again with the timer going down every half hour, from 09.01 until 10.00 or so, depending on the number of days remaining.8.
At 11.00 UTC the countdown goes down to 10:00 UTC.
The next countdown will start in the timezone, which is UTC +1 (or -1).
The countdown will also be accompanied on Twitter by a live countdown timer, as well as a countdown banner.
The clock will be powered by the Twitter app.7am UTC is GMT +2 (or GMT -2) and is the time of day when most people in the world are expected to be awake and online.