c:\@Work\Perl\monks>perl -wMstrict -le
"use strict;
 use warnings;
 ;;
 my $line = 'OD44202,07/01/2015,08/19/2019,08/27/2019,1,07/01/2015,06/30/2019,2015-06-20 00:00:00';
 ;;
 $line =~ s/(\d{4})-(\d{2})-(\d{2})\s\d{2}:\d{2}:\d{2}/\2\/\3\/\1/g;
 print qq{>$line<};
"
\2 better written as $2 at -e line 1.
\3 better written as $3 at -e line 1.
\1 better written as $1 at -e line 1.
>OD44202,07/01/2015,08/19/2019,08/27/2019,1,07/01/2015,06/30/2019,06/20/2015<