What dose this refer too? Is it mating flights and such or something else?
In part. It also involves special training... browns and bronzes are more likely to find themselves in leadership positions, so they have to learn things about that. The fighting techniques for greens would be different than those for bronzes based on size/speed/stamina, as well.
This is from the Weyrling FAQ in m4 of Weyrling training on the website:
Specialized Training Begins (by color and Weyrlingmaster assignment)
Green/Blueriders: Searchrider etiquette and the laws governing Search.
Brown/Bronzeriders: Duty roster training with Weyrleader's Wingsecond.
Goldriders: Weyr personnel and recordkeeping with junior goldrider or Weyrwoman's Second.
And the link:
http://www.triadweyrs.org/faq.php?q=weyrlingm4