Evening dress code in Antarctica

We are new to Seabourn and are in the process of packing. We believe that there have been some recent dress code changes. Our question is regarding the requirements for men. We will be sailing on Antartica.

Are nice looking sweaters acceptable for men in the evening? Do they need to be worn over a collared shirt? Is it the same in the main dining room as well as in the Colonnade restaurant?

We appreciate any help.

No need to answer my question. I just read through the 26 pages on the dress code sticky and found the answer I needed on page 25.