Tracking tenants who are being evicted

Possession - Section 8 and Section 21

I have a possession order for a residential property with 2 tenants.
I am using the services of an HCEO, who is going through the process of transferring the court order to the high court for a writ.
I am then hoping that I will get vacant possession through the work of the HCEO.

At the same time I have a County Court judgement for the amount of £2500 plus daily rent until they leave.

When they leave I do not excpect to get a forwarding address from them! Having researched the parents' address that they gave me when moving in, it looks like the parents have moved out from this address. ( although they have lived there in the past).

Is there anything I can do at this stage, while they are still in my property, and I know where they are, which will facilitate finding them later. (So I can pursue the debt).

I do not want to start any process that will rely on them remaining at the property, as my main concern is to get possession of the house.

I have good reason to beleive that one of them has the funds to pay, so would like to pursue the debt.

Many thanks for any advice.