Both Facts billing and Register billing, how to exclude one of them

Hi,

I have an installation with two different Rate determination, one through register and the other one through facts.

Is there any way (Customizing, user-exit, enhancements, BAdI or anything else) to configure the Billing process in order to exclude one of them at time of the billing run?

e.g. I want my Billing document to contain only lines whose rate is derived from facts, and the register rate should be ignored so that the corresponding lines are not created (even because there are no meter reads for the billing order which makes it implausible).

Thanks,

John