While you may be right there is also the possibility of a bottleneck
along the way.  In the past year, on about three occasions, mail
from the lists I manage was delayed for up to four (!) days for
a period of several days for *some* (not all!) subscribers.
Most recently this happened a few days ago and affected both
myself (in one of my accounts) and several subscribers. I first
noticed the problem when a couple of subscribers wondered why
they had ceased receiving mail.  One of the subscribers received
73 delayed messages all at once.  Imagine how she would have felt
if the flood arrived three days after she signed off?!
 
Once a message has been sent you have no control over the route
it takes or the speed of delivery. I've tried to anticipate such
eventualities by explaining the way listserv works to my
listmembers and ask them to report any irregularities to me
by private mail.
 
Sincerely,  Ingrid Shafer
[log in to unmask] & [log in to unmask]
http://astro.temple.edu/arcc