blending on two levels

Hi,

we have a BW4 live model (M1) and two imported models (M2 + M3).

the imported models are for mapping purpose in the following logic:

1. map dimD with from M2 towards M1 using dimA and dimB

2. for one specific combination of dimA and dimB, multiple versions of dimD can happen. Therefor map dimD from M3 towards M1 using dimC.

I do not know if I could explain our issue here, however we do not know how to do this via SAC.

thank you and best

D