A couple of small optimizations, the real issues seem to be covered already.

Any busy fixed size hashes like %states may be converted to arrays:

use constant bounced => 0;
use constant deferred => 1;
use constant directory => 2;   # et cetera

my @states;
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Regexes like  next if (!/MsgTrace/); should be faster if anchored, I'm just guessing at the values here  next if ( !/^.{52,55}MsgTrace/);