iPhone making millions of DNS queries for akamai.net

I'm running PiHole as a local DNS server on my home network. Over the past several days, I've noticed that my iPhone is performing millions of DNS requests to a2047.dscb.akamai.net over the span of a few hours. This behavior appears to have started about a week ago. I've forced quit all running apps and have restarted the phone, but still see the DNS query being performed by the iPhone, so I suspect it's something related to iOS. I realize that Akamai is Apple's CDN provider, but I'm stumped as to why my iPhone is all of a sudden behaving this way.