code: func (r Billing_Item_Cancellation_Request) GetCancellationCutoffDate(accountId *int, categoryCode *string) (resp datatypes.Time, err error) {
  	params := []interface{}{
  		accountId,
  		categoryCode,
  	}
  	err = r.Session.DoRequest("SoftLayer_Billing_Item_Cancellation_Request", "getCancellationCutoffDate", params, &r.Options, &resp)
  	return
  }
docs: // Services can be canceled 2 or 3 days prior to your next bill date. This service returns the time by which a cancellation request submission is permitted in the current billing cycle. If the current time falls into the cut off date, this will return next earliest cancellation cut off date.
  //
  // Available category codes are: service, server