Shapley Value - Interpretation of a model with threshold cutoff less than 0.5

The Shap Value of a feature equals 0 implies the feature is unimportant & the corresponding probability is 0.5 but if in our model the cutoff probability is not 0.5 but 0.2 then how does corresponding shap value change ?? Does that mean the reference of Shap changes from zero to corresponding less than zero value for ??