I guess the suggested iterruptions are because patients normally cannot keep breathold for a full turn of 60s. So the angle is not really well defined, it’s more given by the length of breath hold the patient is able to keep. With a full turn CBCT (360°) I guess it is ok to stop only twice, i.e. after 120° and after 140°. So you have 2 sections each lasting about 20sec. Hope that helps.