What is "PO ordered amount for hold" source in BPM?

Summary:

Build a rule in BPM in order to be able to route the amount ordered hold notification to different users based on the variation between amount ordered and billed amount

Content (required):

I would like to build a rule in BPM in order to be able to route the amount ordered hold notification to different users based on the variation between amount ordered and billed amount.

For example:

if AMT-ORD hold is applied and (billed amount-ordered amount) < 1000 --> X receives the hold notification

if AMT-ORD hold is applied and (billed amount-ordered amount) >=1000 --> Y receives the hold notification

Is it possible to build such a rule? I couldn't find clear sources to to this. Could I use "PO ordered amount for hold" that I found as an available source.