Promotion Attributes are not work when we defined related product constraint

we found the promotion attibure are not work when the related product have constrain.

Sample:

Demo CP

|_Component A

|_Component B

Demo CP's default attribute AB is 'B'

constraint: Selection of Component A from Demo requires the attribute AB = A

Demo Promotion A

|-Demo CP

Promotion attibute required AB include 'A'

when I add promotion into line item,the 'Demo CP' attribute AB is 'B', this result is not we wanted.