Whether engineers who joined BYD in 2022 need to be recalled depends on the recruitment process adopted by BYD at that time. If BYD adopts the company's formal process in 2022, it will definitely give every applicant a comprehensive and strict ring back tone, including telephone ring back tone. According to the relevant public information, under normal circumstances, the company will adopt a formal recruitment process, requiring every applicant to give a comprehensive and strict reply, including telephone reply. Telephone inversion is a way to communicate with candidates by telephone to understand their experience and ability, so as to help determine whether they are suitable for employment.