As topic says. Neither DisablePromotions or DisableBuiltinPromotions works after upgrading to EPiServer.Business.Commerce 126.96.36.199.
That is strange. I guess you call DisableBuiltinPromotions and still see them? How do you call the code?
My error was module dependancy in my initializer. It was probably changed when the site was upgraded. EPiServer.Commerce.Initialization.InitializationModule was overriding my calls to DisablePromotions and DisableBuiltinPromotions. With proper dependancy everything works as expected.