Changing Distance Intervals in Oracle Internet Expenses

Hi, I am hoping someone can help. I look after the administration of oracle internet expenses for NI Water here in Belfast. Back in April we set up a new instance of Internet Expenses under a different operating unit to separate the processing of claims under different operating units.

One of the mileage rates is governed by distance thresholds and users can claim  45p for the first 5000 miles and then 25p up until the end of the tax year. I unfortunately made a keying error on the intervals when I set up at the rate  and set the interval at 50000. This was only picked up during a recent audit check. I have looked at the ways I could change this but haven't been able to find a workable solution without having to set up a completely new rate.