I am not familiar with the ice cream making process. However, several years ago in the beverage industry, I was tasked with reducing a daily hot CIP that was taking over four hours each day.
We were using a blending system that blended water to syrup then sent to another unit to chill (ammonia plate) and carbonate and then sent to the filler.
Some simple ways that I reduced the time was testing the rinse water for presence of product, cleaning solution, instead of a set time for the rinse.
Another way was to install a hot gas escape on the chilling unit. It was taking a very long time to CIP system to get to the correct CIP temperature due to the ammonia keeping the chiller cold. We had our refrigeration company install the hot gas escape loop and this dramatically reduced the time it took for the CIP skid to heat to the correct cleaning temperature, as all that ammonia was instantly pumped into the surge tank and allowed the chiller to get hot.
We were able to reduce the four hour CIP to 100 minutes. Swabbing and extensive testing vetted the change.
Leo