To reconfigure the account type interest method from fixed to floating, you must first:
It is a mandatory precondition for the successful completion of the process. Therefore, make sure to complete it before attempting to adjust the account type interest method.
Adding a new base rate type is available only over the API. To create a new base rate type with the instant rate application rule, follow the steps of this example in the API cookbook.
To add the fixed value for the base rate you created, follow the instructions in this part of the Base interest rate guide.
To understand how the rate fixing is automatically applied once you have changed the account type interest method from fixed to floating, read this explanation about base rate updates in the BackOffice user guide.