The effect of Reg 42B & changes to annexes or extensions - Public forum - Planning Advisory Service (PAS)

I noticed some confusion as to how exemptions for residnetial anneses or extensions operate. Under Reg 42A, a developer is permitted to apply for an exemption if the development comprises a residnetial annexe or extension. One must satisfy all of the criteria before the authority issues an exemption. However, Reg 42B sub (3) and (3A) are often overlooked by officers given the lack of regular coordination or discussin with planning and enforcement. 

A claim under Reg 42A will lapse where the chargeable development to which it relates is commenced before the authority has notified the claimant of its decision on the claim. So, a developer would be at a loss should they commence material operations before an authority grants an exemption. Interestingly, officers have overlooked the effect of any change post planning permission. For example, exemption for a 7 m deep extension has been grantd but the developer adds 1.5 m and calims they qualify for the exemption. CIL Reg 42B sub (3A) states the exemption rules will not not apply where an exemption for residential annexes or extensions has been granted in relation to a chargeable development and the annex or extension changes after the commencement of that development. There is no definition of what amounts to a "change" and a strict interpretation of the rules would, inevitably, mean any change - minor or major, results in the loss of an exemption under these provisions. Discuss!