I just thought of another option, if you get behind and our schedules don't mesh where I can pick you up.
You can take the 28X bus from downtown to the airport. The bus stops on Grant Street, right near the Federal Building (about a 1/3 of a block toward USX rower from the Federal Bldg.)
You can get the schedule here. Sundays are not as good as weekdays for number of trips on most buses anyway.
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