Hello,hope somebody can help as we pulling our hair out with conflicting advice,

we are flying in to Shanghai from the uk in April,staying 2 nights then cruising from Shanghai Boashan cruise terminal to Japan for 5 nights, we then return to shanghai proceed directly to the airport and fly back to the UK,Blue five star china (china tour specialists) say we can travel on the 144 hour free transit, the Chinese embassy told us to refer to there website which isn't very clear at all and the cruise company directed us to CIBT (worldwide company specialists in visas for tourists) who say we should get a full visa before we travel as they get people calling every day who have been refused entry, the thing that doesn't seem to be clarified on the embassy website is can we enter China twice in a week on the 144 hour free transit.
Would be nice to hear from someone who has done what we are going to do.