Definition rec_copy3_trans (c : Config) (s1 s2 : Site) :=
  mkconfig (S (time c)) (Update_table (dt c) s2 (S (time c))) 
    (st c) (Set_rec_table (rt c) s2)
    (Post_message (inc_dec s1) (Collect_message (bm c) s1 s2) s2 owner).

Lemma rcop3_trans_diff_site : (In_queue Message copy (bm c0 s3 s4) -> s3 <> s4) -> In_queue Message copy (bm (rec_copy3_trans c0 s1 s2) s3 s4) -> s3 <> s4.