Thank you again for your feedback. It was enough to motivate me to book an overnight NYE cruise aboard the Stellar of the Seas. Their check in time at Tuan Chua marina is noon which is compatible with our 10 am scheduled docking time. And they will return us back to the marina at noon the following day leaving us plenty of time to get on board before Solstice leaves at her scheduled time of 5pm.
The only risk I am taking is that if Celebrity decides to alter the itinerary by giving up on Hong Kong, it may well affect our scheduled stop at Halong Bay.