The authority is worried about the lack of "change" funding from the Scottish Executive to smooth the transition to slimmer structures and the impact on staff morale of the most substantial management changes in 30 years.
It makes no sense to rush in before the job-sizing review is completed and the national inquiry into guidance has reported, officials advise.
Christine Dignan, group manager for schools, says that by August next year teachers will have benefited from their full McCrone salary hikes and may be more likely to opt for early retiral and therefore ease the move to revised structures.
Mrs Dignan states: "Since pupil support and the arrangements for its management are clearly integral to the overall management arrangements for the school, it would not be logical to separate this strand from the whole.
In order to avoid a hiatus and maintain effective guidance provision in our schools next session, transitional arrangements are required."
The council is adamant that new management structures must be paid for within the existing staffing budget, although it accepts that job sizing and salary conservation may cause school-level difficulties.
Unions told the authority that the McCrone agreement did not specify reducing the number of promoted posts in secondary.