Release WBS element on Save of Sale Order

Dear All,

Can we release WBS element on Save of Sales order??

Requirement:- Need to release WBS at the time of Saving the sales order. I am not able to find out exit where we can right a code for the release of WBS.

I tried MV45AFZZ - USEREXIT_SAVE_DOCUMENT_PREPARE but during this time XVBAP-PS_PSP_PNR is initial.

Please guide.

Thanks,

Gaurav