I'm not sure how that goes, but I'd guess It's optional. The numbers are a tad different I believe, the T above the numbers is new (used to be on the collar) and the state patch is new. Other than that, they're pretty much the same. The road unis will have Tennessee across the chest...not really sure how I feel about that, but they haven't been revealed yet.
I like 'em. The new # font and state patch is nice. But the chest looks a little too busy, imo. I'd move the adidas logo to the right side opposite of the SEC patch.
Also, the alternate unis will be unveiled Aug. 15th. They will be grey (the new trend I guess), and will be worn for 1 game this year that's still TBD. Possibly at Oregon.