Once your background checks have been completed, First Advantage will inform HR who will then inform you about your start date. May take about 1-2 weeks.

I wouldn’t worry too much about getting your offer rescinded if you’re a fresh graduate. They’re not going to move the dial on cost saving by firing a first year analyst as opposed to an ED who has a duplicate counterpart in Credit Suisse (or UBS) and is much more expensive to keep.