...
You have the option of allowing the system to roll forward the frequency of future invoices without affecting the existing invoices. Ordinarily, when you enable roll forward invoicing, going into the fourth week, the first three weeks would be credited back and re-invoiced together with the fourth week as a month. If, however, you choose decide to Override Rolldown on Roll Forward, the first three weeks will not be credited back, and the fourth week will generate another weekly invoice. Then the remainder of the rental period will be billed at the monthly rate, starting with the fifth invoice. Any unused days that are billed as part of this month will be credited back after the equipment is taken off rent. See Set up Global Rental Parameters. for the steps involved in choosing this option.
Adjusting Rates
When you choose to decide to allow roll forward invoicing, another checkbox is enabled that lets you also choose specify to credit back the difference between the cost of the rental at the old rate and the cost of the rental at the new rate. For example, if the cost of three weeks of rental is $300, and the cost of a month of rental is $250, rolling forward will create a $50 credit to the customer. Marking the Auto Adjust Rates checkbox will adjust the old rate to equal the new rate; this way, the system reads that there is no balance due to the customer and does not create a credit. This is beneficial if the new rate is cheaper than the old one, and you want to adjust the invoicing frequency of the previous invoices without affecting the cost. You can select this option on any window where you enable roll forward invoicing.
...