DPS arbitration

Tenancy Deposits

Hi,
I am registered with the DPS and I have applied for their arbitration
in a case where the tenant left before the end of the six months term
of the contract with 1 month's notice.
Not being sure of my position, I have applied for arbitration on the deposit because from clause 5 on termination of the contract it looks as if I am due at least the next month's rent.
However, the tenant does not accept the arbitration procedure and the DPS say the cannot do anything unless he does; apparently all I can do is wait for him to start legal action to reclaim his deposit and go to court (he says I shall hear from his solicitor).
Can anyone help to clarify my position?
Incidentally, I have contacted Landlord Action, but they said they would not get involved in this sort of dispute.

Thanks

Riccardo Cuminetti