There are two modes / options to define a time zone that meet this requirement.
First, please find more information about how to set the time zone in ConfTool here:
Time Zone Offset.
To define the time zone that is used by your ConfTool installation for all deadlines, please go to:
Overview => Settings => Main SetupUsing the option "Time Zone" (see image), you can choose the zone GMT-11 (also known as UCT-11, which is a time standard, while GMT is a time zone). GMT/UCT-11 has here the function like the International Date Line West (IDLW), an imaginary line on Earth's surface defining the boundary between one day and the next officially has.
In the input field "Time Zone of Your Conference" you can define the acronym for the time zone selected, in this case e.g. IDLW or AoE (Anywhere on Earth).
Actually, IDLW and AoE are defined as GMT/UCT-12, but the list provided by Unix/Linux doesn’t contain UCT-12, which doesn’t really matter as UCT-12 / IDLW / AoE only applies to Baker Island and Howland Island (uninhabited islands belonging to the United States). Therefore UCT-11 is nearby the International Date Line and should cover any of your authors and participants.
Some details about this time zone are available in this Wikipedia article
UTC−11:00 and on this
List of all time zones.