Has anyone create a contract billing invoice from a Work order

Hello

We have a business requirement to have a customer invoice created thru the contract billing module .

Here is our set up:

1) we have a job master and a contract master

2) We use the Time and Material billing lines in contract billing

3) When the Work file gets created , I can see in the F4812 that our wo # is sitting in the SUBLEDGER field as expected

4) Can I create a contract billing invoice from a SUBLEDGER number with the R52121 ?

Has anyone done this ?