Since the timing of set and promo releases has changed in recent years, this may be something we need to revisit in order to codify what the policy going forward will be.
I believe the policy for State, Regional and Nationals is still that you can only use a new promo for a tournament level "above" the tournament where you received it. For example, Esau was not legal at last year's Regionals, but was legal for Nationals. We made an exception for Noah's Ark last year because the Ark and the Flood Survivor theme were released well in advance of Nationals (giving people time to become familiar with it if they wanted to use it and/or be prepared to face it at Nationals).
I will add this issue to the list of topics that the Elders are discussing.