The second regex clears the capture from the first. 
while (<DATA>) {
  if(/START/.../END TIME (.+)/) {
    my $time = $1;
    next if(/START/ | /^\s*$/);     
    print $time, qq{\n};
  }
}
__DATA__
START
END TIME 123
START

END TIME 456

[download]
123
456

[download]

In reply to Re: saving matching pattern with flip-flop operator by wfsp
in thread saving matching pattern with flip-flop operator by raja_infy

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