Well I think that it sets the time to GMT.

Lets see, searching Class::Date for "gmdate"

use Class::Date qw(:errors date localdate gmdate now -DateParse -EnvC);

$date = gmdate "2001-11-12 17:13";

You can create a date object by the "date", "localdate" or "gmdate" function, or by calling the Class::Date constructor.

"gmdate $x" is equivalent to "date $x, $Class::Date::GMT_TIMEZONE".

It could be