I'm arriving Beijing Terminal 3 by Thai Airways at 15:50pm. Planning to take the Air China domestic flight to Xian at 18:30pm Terminal 3. As they're both different airlines, I assume I'll need to go through arrival immigration and claim my luggage. Do I need to do a check-in for the domestic flight and go through the immigration again? Will I have sufficient time to do all the check-out and check-in to catch the 18:30pm flight?
Please advise. Thank you.