message: Don't start an era before its start timestamp.
diff: @@ -258,7 +258,7 @@ where
  let results = if should_activate {
  let secret = HighwaySecret::new(Rc::clone(&self.secret_signing_key), our_id);
  - highway.activate_validator(our_id, secret, timestamp)
  + highway.activate_validator(our_id, secret, timestamp.max(start_time))
  } else {
  Vec::new()
  };
  