Umm, that does exactly the same thing:

use Data::Dumper;
use Test::More qw(no_plan);

$AoH[0]->{heading}->[3]->{item}  = 'eee';
print Dumper @AoH;

$BoH[0]->{heading}->[3] = {item  => 'eee'};
print Dumper @BoH;


is_deeply(@AoH,@BoH,"They're the same");
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Output:

$VAR1 = {
          'heading' => [
                         undef,
                         undef,
                         undef,
                         {
                           'item' => 'eee'
                         }
                       ]
        };
$VAR1 = {
          'heading' => [
                         undef,
                         undef,
                         undef,
                         {
                           'item' => 'eee'
                         }
                       ]
        };
ok 1 - They're the same
1..1
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