Do I need to update my bank book and provide a new bank certificate for a one-year extension based on marriage to a Thai citizen?

I always update the bank book the day I go back after the consideration.

Don’t take a bank letter, but this is Samut Prakhan immigration

If you mean you already applied for a 1-year extension and you are on the under-consideration period now, then go to the Chaengwattana office to get the stamp for the rest of the 1-year extension, you don't need anything other than your passport. But bringing the updated bank passbook is not a bad idea.

If you mean you are applying for a one-year extension, you need a bank letter and a transaction report up to 7 days old. You don't have to get new ones if it's issued within 7 days. You also need an updated bank passbook, original.

You put a small amount of money into your account and then update the bank passbook on the day you go to the CW office so that the officer can see your funds are in your Thai Bank account on that day.