[Exim] Spamtrap, one copy for recipient, just one needed

I have set up a router+transport to move spam to an account for further
review.

at data acl

...

  warn   message = X-Spam-Flagged: true
         spam = nobody
         log_message = spam score="$spam_score" rcpts="$recipients"
subject="$h_Subject:"
         hosts = ! +relay_from_hosts
         control = fakereject

...

the router (i have placed it as first)

spamtrap:
driver = redirect
condition = ${if def:h_X-Spam-Flagged: {1}{0}}
file_transport = spamtrap_delivery
data = /home/vmail/mydomain.com/spamtrap/Maildir


the transport

spamtrap_delivery:
driver = appendfile
envelope_to_add
return_path_add
mode = 0600
maildir_format = true
create_directory = true
directory = /home/vmail/mydomain.com/spamtrap/Maildir
user = foo
group = bar

1. If someone send spam to multiple recipients, I got in spamtrap one
mail per recipient, is it possible to get just one copy per spam
message?

2. Can I use the value of router data option in the transport to avoid
the repetition of the path of the mailbox in directory?

Regards
mike