I'd be curious if the timing of this being Easter weekend has anything to do with this. Many people had the stat holiday off and it'd work out well to swing by the polling station on their way to visit family.
Is there any benefit to advanced voting? I mean, it's not busy at my local voting station on election day (at least not historically), so that's when I plan to vote.
It helps people who are working or traveling on election day. It makes voting easier for people with disabilities and reduces long lines on election day, etc etc etc.
tl;dr Encouraging more people to participate in an election is a good thing.
You might be unexpectedly sick, hospitalized, dead, in jail, or otherwise unable to vote on election day. Early voting lets you avoid unexpected issues.
Every election seems to break a new advance voting record. I think that the only thing really happening is that advance voting is becoming more mainstream. When I was a kid, it was something done by people about to go on holidays or being impossibly unavailable on election day. Now, it's pretty common among the general populace, even if they can make it out on election day.