Just wanted to say thanks to everyone for their help on this. I think I've finally got there now. For the record the code I'm using is as follows. I'm converting the datetime into Australia/Sydney timezone before doing the comparison. 
use DateTime::Format::DateParse;

my $p1 = shift;
my $p2 = shift;

my $first_dt = DateTime::Format::DateParse->parse_datetime("$p1");
my $second_dt = DateTime::Format::DateParse->parse_datetime("$p2");

my $first_dt_syd = $first_dt->set_time_zone('Australia/Sydney');
my $second_dt_syd = $second_dt->set_time_zone('Australia/Sydney');

my $diff =  $first_dt_syd->delta_days( $second_dt_syd )->delta_days;

[download]

Thanks again.

In reply to Re^3: How to compare date/times in different timezones? by philled
in thread How to compare date/times in different timezones? by philled

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