This is how I'd do it (albeit without using OO Perl):

use List::Util 'shuffle';

my @bag = shuffle qw( A B C D E );
my @embargoed = pop @bag;

while ( 1 ) {
   my $time = ( localtime )[ 0 ]; # seconds
   sleep 1;
   if ( $time >= 55 ) {
     push @embargoed, pop @bag;
     push @bag, shift @embargoed if @embargoed > 2;
     @bag = shuffle @bag;
     sleep 5;
  }
  print "$time @embargoed\n";
}

[download]

NB: For testing porpoises, I've substituted seconds for minutes and minutes for hours. Adjusting this (including sleep times) is left as an excercise...

Update: Simplified code (and explanation). Minutes don't matter!

In reply to Re: Embargo algorithm by Not_a_Number
in thread Embargo algorithm by Anonymous Monk

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