&LISTNAME  is  either the  short  or  long name  based  on  the value  of
"List-Address="  and/or   its  system   default.  By  default   the  long
("List-ID=") name  is used  if present. Typically  on non-VM  systems you
don't bother with "List-ID=" and only have one list name.
 
You can  replace &MYNAMES  et al  with an arbitrary  value using  the .SE
instruction (which should be in the  list owner's guide). This only lasts
for the duration of the particular message you are sending, of course.
 
  Eric