Seeing issues with hackerweb.app and substack.com too. They don't share upstream DNS (and I'm not sure heroku's homepage has the same DNS provider as customer

Seeing issues with hackerweb.app and substack.com too. They don't share upstream DNS (and I'm not sure heroku's homepage has the same DNS provider as customer domains). NS matches SOA for each of these domains. SOA heroku.com. 1h00m00s "dns1.p04.nsone.net." "hostmaster.nsone.net." SOA hackerweb.app. 1h00m00s "olga.ns.cloudflare.com." "dns.cloudflare.com." SOA substack.com. 1h00m00s "ali.ns.cloudflare.com." "dns.cloudflare.com."