Before returning, the SZ-12 spacecraft will carry out orbiting and radial rendezvous tests to prepare for SZ-13 mission. Actually it should be the TZ-2 will detach from the back and switch to front dock. TZ-3 will take TZ-2 place to rendezvous at the back. Then radial rendezvous test to rotate TZ-2 to the side will be performed. All these tests will take place after SZ-12 return and before SZ-13 dock with the CSS in Oct.
