#!C:/perl/bin
use strict;
use warnings;

our $newdate = 0;
our $string = '<a href="SERVER122007/intranet.htm" target="_blank">Dec 2007</a>';

$string =~ /.+?"SERVER(\d{6}).+blank">([A-Z,a-z]{3}\s\d{4}).*/;

our $ds = $1;
our $monyr = $2;  # changing this may require a dispatch table or a Date::xxx module

print "\nRaw \$ds is $ds\n";
print "\$monyr is $monyr\nCode to modify this left as exercise (hint above) for the OP\n\n";

if ( $ds =~ /(\d\d).*/) {
   our $check_yr_change = $1;
   if ($check_yr_change == 12) {
      changeyear($ds);
   }
   else {
      print "OK! It's not yet time to change the year\n\n";
      $newdate = sprintf( '%.2x',(substr($ds,0,2) +1 ) ) . substr($ds,2,4);
      print "\$newdate is: $newdate";
   }
}

####### sub

sub changeyear {
   use vars qw($mo $oldyr $newyr);
   $mo = "01";
   if ( $ds =~ /\d\d(\d{4})/) {
      $oldyr = $1;
      print "\$oldyr: $oldyr\n";
   }

   $newyr = ( $oldyr + 1 );
   $newdate= ($mo . $newyr);
   print "\n\$newdate in sub is: $newdate\n";
}

=head OUTPUT
for <a href="SERVER072007/intranet.htm" target="_blank">Jul 2007</a>:

   Raw $ds is 072007
   $monyr is Jul 2007
   Code to modify this left as exercise for the OP

   OK! It's not yet time to change the year

   $newdate is: 082007

and for <a href="SERVER122007/intranet.htm" target="_blank">Dec 2007</a>:

   Raw $ds is 122007
   $monyr is Dec 2007
   Code to modify this left as exercise for the OP

   $oldyr: 2007

   $newdate in sub is: 012008
=cut