Whenever it is charged that any person has engaged in an unfair labor practice within the meaning of paragraph (4) of subdivision (d) of Section 1154, the board is empowered and directed to hear and determine the dispute out of which such unfair labor practice shall have arisen, unless within 10 days after notice that such charge has been filed, the parties to such dispute submit to the board satisfactory evidence that they have adjusted, or agreed upon methods for the voluntary adjustment of the dispute. Upon compliance by the parties to the dispute with the decision of the board or upon such voluntary adjustment of the dispute, such charge shall be dismissed.