SAP SD deferred revenue recognition with periodic billing plan and order related billing

Hi Experts,

I am facing an issue to map my client's requirement in the system, my client need that

1) they should be able to generate billing for a sales order on monthly basis, irrespective of delivery document.

2) They should be able to deliver the goods later based on stock availability.

3) They want to generate deferred revenue, which they can pass to accounting using VF44, post actual goods issue of the goods.

Below is what I have done to achieve this.

- At header level assigned a billing plan (periodic billing plan)

- At item level, I have used billing relevance "B" and revenue recognition category "B".

somehow it is not working, can somebody please guide me on

1) Whether this requirement can be fulfilled using standard SAP,

2) If yes, what is that I am missing here.

Thanks a lot for your help