This is the first year we've not been there for the race weekend (they moved it) and I can confirm that it's pretty much a mess to get to anywhere on Sunday morning. We tried to get to AK from BWI last year. First, tried to get a bus. The buses couldn't even get TO the resort. We managed to get connected to an Uber that was dropping someone off. He warned us that it was going to be a long trip. When we got out we realized why, it was gridlock. Everything was stopped, buses, cars, all of it. Cars did managed to get through a bit better only because they were able to move in and out of the buses a bit easier. The buses just sat in a long line. At least we figured out why no buses could make it to the resort.
If you don't have to do rope drop, I would make it a lazy resort morning, wait till noon
Or go to MK. MK was the only park that could be accessed by bus that morning. It was also the only bus that made it to the resort