If an employer determines that English competency is a business need, at what point can...

Fornew hires, employers can include language requirementsimmediately— but only if they can demonstrate that English proficiency is abusiness necessity(e.g., safety, communication, customer service).

Extract from HRCI-aligned HR knowledge (Risk Management):

SPHR candidates must ensure “job requirements are defensible under EEOC and Title VII guidelines.” Language must be tied to business necessity, but is permitted forfuture recruiting effortswith appropriate documentation.