I think the what the local police department asked my in-laws to apply right before the before baby leaves for US is the 離境證, but at that time the 旅行證 is already expired, will this going to be a problem? Since the 臨時戶口 is valid as long as the 旅行證 is valid.
If you don't mind, could you please tell me if your son stayed in China longer than the time allowed in his 旅行證 without have the 旅行證 extended?
Thank you again, good night!