How does SAP calculates tolerance lanes with ex-post outlier correction ?

Hi

I would like to know how SAP calculates upper and lower limit with an ex-post outlier correction.

In enclosed file I added an example but this does not match our expactation.

Formula for upper and lower limit = Ex-post forecast +- Sigma * MAD

and MAD(t)= (1-Alpha)*MAD(t-1) + Alpha * |V(t)-P(t)|

Initial periods =3

Alpha is 0.3 and Sigma is 1.5

Does any of you have experience in calculating these upper and lower limits ?

Thanks for your advice

Fred