The Recurve and Modern Recurve Rules were updated on the TAS Rules. Here's the link to rules.
The Main Differences
Recurve Class the riser is wood, micarta, phenolic, G-10 or a combination. No metal risers and no adjustable style side plates and wood arrows only shooting off the shelf.
Modern Recurve Class is any riser material and any arrow material shooting off the shelf.
TAS Classes for Adult and Senior
Hill Style Bow (World Championship Only)
TRADITIONAL BOWHUNTER WORLD CHAMPIONSHIP
Farmland Conservation Club, Winchester, Indiana
PUBLIC LAND HUNTER
John Schulz Straight Shooting and Bowhunting Graduate