Trilio - bill based on number of backed up instances

We would like the option to bill based on the number of instances being backed up within a workload.

Currently we can apply a price plan to the Trilio storage used or a workload being present; It would be useful to have the option to bill based on the number of instances being backed up (for example if a workload contains multiple instances).

It may be possible to do this if we could filter instances based on the existence of a property as Trilio looks to add the workload details to the instance properties:

"properties": { "workload_id": "c1b457e4-8bb7-42ad-a2af-ede3397b3f71", "workload_name": "workload-job-name" },