Hi!
 
> Just put the new address in your list header  Owner= new address
>
> Naturally you'll need to do this while you still have the old address.
 
And naturally you should you *add* it as an owner, and test mail from
the new address before relying on it working!
 
You might ask your new ISP if their mail system has any surprises in
store for mailing list type activities (identifying users by the mailid
attached to mail messages).
 
Peter