The newly-named Carrickfergus Academy will operate across a split site until a new build is available.
In a newsletter to parents, the interim Board of Governors for the school - an amalgamation of Downshire School and Carrickfergus College - highlighted that pupils would be taught across both campuses using a 'junior school' and 'senior school' model.
"Neither school building is large enough to accommodate the merged school population of approximately 1250 pupils. That means the new school will operate on a split site in the interim though it will be treated as a priority by the Department of Education for a new state-of-the-art building," the newsletter added.
"In the meantime, the Board is seeking to make decisions that best facilitate the education of pupils using the existing buildings at North Road and Downshire Road.
"In September 2018 pupils will be accommodated at these campuses on the following basis:
Year 8 - Downshire Road campus;
Year 9 - Downshire Road campus;
Year 10 - Downshire Road campus;
Year 11 - North Road campus;
Year 12 - at the school they currently attend;
Year 13 - North Road campus;
Year 14 - at the school they currently attend.
"The Board, in agreement with the current principals, believes this is the best option to limit the disruption to pupils who are taking GCSE or A2 exams in June 2019.
"From September 2019 all pupils in Years 12 and 14 will be accommodated at the North Road campus."
Meanwhile, suggestions for the new school name were invited from the pupils and staff of both schools, with Carrickfergus Academy chosen by the interim Board of Governors at its meeting last Thursday evening.
“A new post-primary school for Carrickfergus was first mooted five years ago and, now that the decision has been made to amalgamate, we are moving forward at pace,” said Reverend Harry Coulter, co- chairperson of the interim Board of Governors.
“The joint school council produced a shortlist of six potential names for the new school and Carrickfergus Academy was the favourite among pupils and staff, and the unanimous choice of the governors."
The new school will educate approximately 1250 pupils and offer the full range of subjects at GCSE.
“[It] will offer an increased range of subjects and widen opportunities to participate in extra-curricular activities which it is hoped will encourage more pupils to stay on in school after GCSE,” added Mr Coulter.
Last week, staff from both schools got together for in-service training in preparation for the amalgamation.
Alan Winsby, co-chair of the interim Board of Governors said: “The staff are already putting plans in place for September 2018. At last Monday’s meeting, they had the opportunity to meet the new governors as well as meet the colleagues they will be working with in Carrickfergus Academy.
"The amalgamation will bring considerable benefits to the young people of Carrickfergus. There will be greater subject choice, a larger pool of specialist teachers, and pupils with needs will benefit from the support of an enlarged Special Needs department.”
By the end of November, the interim Board hopes to have selected a principal designate for the new school, whose challenging task will be to make the vision a reality by September 1, 2018.