Here are a couple of useful OO type functions

%taps;
$taps{'T1'}++;

print "New taps, same level\n";
print new_tap('T1')," " for (0..15);
print "\nNew taps, new level\n";
print new_level('T1')," " for (0..30);


sub new_tap {
    my $tap = shift;
    my ($root, $end)= $tap =~ m/^(\w+?)([\d]+|[A-Z]+)$/i;
    my $new;
    {   $new = $root.$end;
        if (exists $taps{$new}) {
            $end++;
            redo;
        }
        $taps{$new}++;
    }
  return $new;
}

sub new_level {
    my $tap = shift;
    my ($root, $end)= $tap =~ m/^(\w+?)([\d]+|[A-Z]+)$/i;
    my $suf = ($end =~ m/[0-9]/) ? 'A' : '1';
    {   $new = $root.$end.$suf;
        if (exists $taps{$new}) {
            $suf++;
            redo;
        }
        $taps{$new}++;
    }
  return $new;

}
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cheers

tachyon

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