Question, About the yellow flag?

[bugsoup]

no nascar changes its rulings all the time. on friday nights trk. race johnny benson went below the yellow line and past a trk to improve his position. nascar says a race car can not go below the yellow line its against there rules, and if you do you will be penelized. benson was not.
also the rule is to be read if there is a wreck the yellow flag will be waved. and field frozen. sometimes they do it and this last time was the first time in about 3 years that i seen them not throw the flag. some people say it was because it was the last lap. but races over the last few years it did not matter it was last lap. they froze the field.