You are not giving enough info - what does the 'next indicator' look like? I will go ahead and assume one.

Pointers - pass args to subroutines, don't rely on globals. Second, don't name a filehandle DATA, because there is already a built-in DATA filehandle. Third, use a regex on a scalar that contains the file contents, not a for loop on an array.

Check this out:

use strict;

my $contents = do {local $/; <DATA>};
print get_chunk($contents);

sub get_chunk {
   my ($contents) = @_;
   my $start = qr|========= Summary of bfpr_catfl results ===\s*|;
   my $end   = qr|========= end ===\s*|;

   my ($chunk) = $contents =~ /$start(.*)$end/s; 
   return $chunk;
}

__DATA__
you won't see this
or this
========= Summary of bfpr_catfl results ===
you will see this
and this
========= end ===
you won't see this
or this
or that
[download]

See perlre for more info on regexes and the 's' option and perlop for info on 'qr'.

UPDATE:
I notice you tend to group variables together with a common prefix - BFPRCONS - you should try a global hash (not all globals are bad):

my %BFPRCONS = (
   filename => 'whatever_the_name_is',
   count    => 0,
   start    => qr|===== summary blah ===|,
   end      => qr|===== end blah ===|,
);

# then you could inc the count like so:
$BFPRCONS{'count'}++;

# you could set the file name like so:
$BFPRCONS{'filename'} = join ('_',$job,$junk1,$etc);
[download]

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
F--F--F--F--F--F--F--F--
(the triplet paradiddle)