Rigor of coursework, extracurricular activities, volunteer work, work experience, first generation, geography are all considered in admissions, according to their CDS.
No “Rolling Admissions” boxes are checked, as of last year’s admission class.
Given that their “Dates and Deadlines” page has specific dates and no mention of rolling admission, I’d trust that over “ A person who I would think was in the know” unless that person is in the admissions office.