Although several companies are mentioned in this article, XPO is also discussed so I am posting it here.

Truckers have asked the National Labor Relations Board to intervene in a string of cases in which the drivers say they have become victims of workplace retaliation, including termination, as they pushed for collective bargaining and better working conditions.

The truck drivers allege that employers use tactics such as withholding jobs or triggering calculated dispatch delays that leave truckers waiting for hours at loading docks for work. The drivers claim the lack of loads given to them are not enough loads necessary to make a living or pay expenses owed on leased trucks.

The NLRB, an independent federal agency charged with enforcing the National Labor Relations Act, which protects the rights of private-sector employees, has interceded in some of the cases.
https://www.trucks.com/2017/03/07/tr...s-nlrb-claims/