Legal disputes over the purchase by Columbus Capital of the Origin wholesale mortgage distribution business from ANZ are warming up, with possible consequences for a planned sale of mortgage-backed bonds by Columbus.Pioneer Mortgage Services is one mortgage manager that is escalating its dispute with ANZ and Columbus Capital over fees Pioneer claims it is owed by the bank and Columbus.Pioneer, a Gold Coast-based firm, contends that Columbus is demanding additional payments of around A$25,000 a month in the form of an increased "delivery rate."A statement of claim lodged with the Supreme Court of New South Wales shows Pioneer projects the present value of the damages to be $570,000.Pioneer is seeking a declaration that the correct delivery rate is the bank bill swap rate plus seven basis points and 75 bps on all loans "introduced and managed by the plaintiff that are funded by ANZ."Pioneer is also contesting the right of ANZ to transfer, or novate, the mortgage management contracts to Columbus.