39.1 For the purposes of this Agreement, Authority Events of Default means any of the following events or circumstances:
39.1.1 the Authority is in material breach of its obligations under Clause 9 (Nature of Land Interests) (other than as a consequence of a breach by Sub-hubco of its obligations under this Agreement) and such breach materially adversely affects the ability of Sub-hubco to perform its material obligations under this Agreement for a continuous period of not less than thirty (30) Business Days; or
39.1.2 the Authority fails to pay any sum or sums due to Sub-hubco under this Agreement (which sums are not in dispute) which, either singly or in aggregate, exceed(s) the amount of the Monthly Service Payment from time to time and such failure continues for thirty (30) Business Days from receipt by the Authority of a notice of non payment from Sub-hubco; or
39.1.3 the Authority is in breach of its obligations under Clause 57.4.