  With 'M' command, you  can  give  your local bbs from which you
regularly take your mail.
  If any user send a msg to you and doesn't specify the bbs field,
this msg will sent at your local bbs.
If for example you type M SV7AIZ then your home bbs becomes SV7AIZ.
Suppose that  your call is SV7QI and bbs receives a mail like this
       S SV7QI,
then it will go and stay at SV7AIZ bbs.
The  header  of  this  mail changes to
   S SV7QI @ SV7AIZ.
Nothing will happen if we receive the following
   S SV7QI @ SV1IW
because the bbs field has been defined.
 
 