qty hold: logged does.not.equal qty hold queue ?

[Len Conrad]

I'm testing a new filter, so I HOLD matching messages, then inspect them to 
either release or delete them.  

egrep -ic "hold: " /var/log/maillog
298

but in mailq:

mailq | mailq-oneline.pl | egrep -ic "! "
35

cross checking:

find /var/spool/postfix/hold -type f | wc -l
      35

In case I forgot I cleaned the queue:

egrep -ic "postsuper.*removed" /var/log/maillog
3

Why the 250+ diff between HOLD: log lines and hold queue files?

Len