KnowBeLove T.,
If you want help with your problem you need to provide more detail.
Typically, a client can complain about work done under any hourly contract but Upwork will pay the freelancer with or without the client paying Upwork for the amount due under the contract within certain limits, as long as the freelancer has properly tracked all billable work time using TimeTracker.
Why are you considering arbitration? Is Upwork not paying you because you didn't track your work time correctly and the client is refusing to pay you?
If this is true, the client has no incentive to agree to go to arbitration. So arbitration may not be an option for you - if the client doesn't agree to arbitration you can't force them to participate.
This is very different than arbitration under Upwork's rules for fixed price contracts, where Upwork's independent arbitration arrangement is only available to the freelancer if (s)he first pays the fee for arbitration, in which case the client must then either also pay their share of the arbitration fee or lose the dispute.).
If the freelancer doesn't pay for arbitration, the freelancer loses the dispute by default. If the freelancer pays for arbitration but the client doesn't agree to pay for arbitration, the fee the freelancer has paid is returned to the freelancer and the client loses the dispute by default.
If the dispute goes through Upwork-related arbitration then the arbitrator's decision is final. Neither freelancer nor client can pursue a different arbitration or even go to court for the same dispute - that is typically an important proviso of any arbitration.
Good luck!
