‘Shall’ when be construed as ‘may’ and vice versa

(2022) 8 SCC 352 Vidarbha Industries Power Ltd. v. Axis Bank Ltd. "Ordinarily the word "may" is directory. The expression "may admit" confers discretion to admit. In contrast, the use of the word "shall" postulates a mandatory requirement. The use of the word "shall" raises a presumption that a provision is imperative. However, it is well settled that the prima facie presumption about the provision being imperative may be rebutted by other considerations such as the scope of the enactment and the consequences flowing from the construction." [para 64]