Hi there! Once your sod is established, you can treat is as you would any established lawn. So if you planted back in July you should be good to go. How much traffic does your lawn get?
Lawns with low traffic and well draining soil may only need to aerated every few years.
NG Turf posted an article a while back that states a quick/easy way to test to see if a lawn needs aeration would be when the ground is moist, try and push a screwdriver through the grass and into the soil. If the ground is too hard for the screwdriver to penetrate, then you should aerate.
Hope that helps! Cheers!