Proof using.
intros.
unfold packets_ge_prevTerm. intros. simpl in *. find_apply_hyp_hyp.
intuition.
- unfold packets_ge_prevTerm in *. eauto.
- subst. exfalso. match goal with H : _ |- _ => apply H end.
repeat eexists; eauto.
Qed.

(* Specifications: *)
Theorem handleTimeout_not_is_append_entries :
forall h st st' ps p,
handleTimeout h st = (st', ps) ->
In p (send_packets h ps) -> ~ is_append_entries (pBody p).