If a lending institution adjusts the rate of interest charged on loans on common adjustment dates (such as the first day of January, April, July and October, or less frequently) rather than adjusting the rate of interest on an individual quarterly (or less frequent) interval measured from the date of the loan, the lending institution may on any common adjustment date increase the rate of interest charged on a loan made within 25 days before that common adjustment date only if prior to the consummation of the loan the lending institution provides notice of the increase and the new rate of interest to the person who is to be primarily liable on the loan. In no case may the rate be adjusted more than once within any three-month period.