Plan driven open PR quantity

Hi All,

I've got the following scenario in PDP (SRM extended classic scenario):

1. PR created in backend with quantity 10 unit

2. Run program bbp_extreq_transfer in backend to transfer the PR

3. SC created in SRM with quantity 10

4. Change PR quantity to 15 unit in backend

5. Run program bbp_extreq_transfer in backend to transfer the PR change

6. Neither new SC created nor quantity change happen in SRM

What the setting required in order to cater the balance of 5 unit in SRM?

Thanks.

Has.