Chris is right; the 7 day list is a quick look at limited data with a computer program. It's continually being revised as seismologists examine the data and revise the parameters.

But remember, I'm years out of date on this. When I was on the alert system we used a 36" globe and a big compass to get locations.

A better source is the ANSS or NEIC online database, where "final" solutions are archived. And even those are subject to revision.

Roger