。
She got promoted ahead of her seniors.
Literal
She [topic-は] seniors [object-を] overtaking got-promoted.
追い越す (おいこす) literally means 'to overtake' or 'to pass,' used here figuratively for surpassing colleagues in career rank. 昇進する (しょうしんする) means 'to get promoted.' In Japanese workplace culture, the 先輩/後輩 (senior/junior) hierarchy runs deep — promotion based strictly on merit rather than seniority can be socially delicate, as it disrupts the expected order.