CHANGES await both the Hongkong Academy For Performing Arts (APA) and its 314 exuberant graduates at the conclusion of this academic year. The Director of the Academy, Mr John Hosier, returns to England on retirement in August. He will be succeeded by Mr Lo King-man, currently deputy director of the Hongkong Polytechnic and vice-chairman of the Urban Council. Drama will be offered as a degree course this September, and there is the promise of a new television studio. At this year's seventh graduation ceremony at the APA's Lyric Theatre, Mr Hosier painted a positive picture for the graduates. ''So far the prospects for our students have been healthier than with similar institutions in most other countries. ''I would predict that within five years, Hongkong will have both full-time Chinese and Western opera companies.'' This year the School of Technical Arts in Theatre saw 80 graduates, the section of Television and Film 40, the School of Music 91, the School of Dance 64, and the School of Drama 39. Kevin Chun Kai-wai, who holds a professional diploma in drama, majoring in acting, is confident about the future although he has no job offer yet. ''One has to count on chance in this field,'' the 21-year-old said. ''I am a little uncertain right now, but I'm still young and I can wait for a good opportunity to come.'' Technical Arts graduate (Theatre) Leung Kwun-tai, 24, majored in stage management and has already joined the City Contemporary Dance Company as assistant stage manager. ''Hongkong can absorb about 50 per cent of APA students in this major. Six out of eight of my classmates have already been hired,'' Kwun-tai said.