No, they do not. The school can choose to administer CBT makeup test sessions at any time after the school's/grade level's primary CBT administration is ended.
As soon as a CBT school has completed its regular two CBT sessions, the school may begin administering CBT makeup sessions anytime within the standard six-day CBT test window. The school may also decide to wait for the CBT makeup period. This is a local decision that can be determined by the district/school.