Main purpose of aeration is to loosen soil to allow better root growth. In cool season grasses, root growth is at it's prime from Sept to May/June. Only time root growth stops is if ground is frozen. Best time for aeration is as early as you can in the root growing time frame - so yes, now would be more beneficial than spring.
Another benefit in fall aeration further north is that the soil has more pore space, therefore more space to hold water. Then when the ground freezes, there is further aeration from the freeze/thaw process.
North central Indiana
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