I would think December is better. For one they will have eaten all November to fatten up and two, they will start developing some eggs for spawning in December (which not too many people know this, but it is true). I personally don't fish Cumberland for Smallies but the actual fish growth and eating habits are not too different from Dale Hollow, where I do fish for Smallies. All 3 of my 6 pounders have came in December and approximately 25 of my 35 that were over 5 were caught in December plus a bulk of my 4+ pounders. More fish and bigger fish are caught in December for me than any other month of the year.