Cashmere High appointed Stradwick, who is deputy principal at Auckland's Mount Albert Grammar School, to the role in late July after Eccleton was named Christ’s College's new executive principal in May.
Eccleton will also start his new role in term four. He was Cashmere High principal for five years but worked at Christ’s College from 2016-19 as its assistant principal - curriculum.
Cashmere High board of trustee chair James O’Connell said the vacancy attracted a "significant list of applicants".
"John is an outstanding leader with a passion for learning, and the vision, experience and skills to lead our school into the future.
"John comes highly recommended from his current role as a deputy principal at Mount Albert Grammar School."
O’Connell said Mount Albert Grammar is renowned for strong academic performance, tradition, cultural encouragement, high-performing sports, and technological advancements.
"John is a former head boy of Mount Albert Grammar, with years of teaching and leadership experience in New Zealand and Asia," O’Connell said.
"John's educational philosophy is centred on the belief that young people's character and resilience are shaped through challenges, which should be faced with the support of teachers, family, and key community members.
"He recognises that each learner has unique strengths and needs, and he emphasizes the importance of professional relationships in a creative, inspiring culture of ‘high expectations’ to create the right opportunities to equip young people with the knowledge, capabilities, and character required for a meaningful life.
"John’s past performance has been a testament to his belief, and he will arrive at our school knowing that he will have our confidence and support. We are deeply grateful that John, his wife, Anna, and their three sons have chosen to join our community. Their enthusiasm and commitment are truly appreciated."
O’Connell said Ms Smith will continue as acting principal during term 3.
"These are exciting times, and the board has considerable expectations and hope for the future of our outstanding school and community."
