"It takes less than five seconds for your address to be harvested and scanned. The entire scan takes less than one second and scans over 100 common TCP and UDP ports. "
OK. I'd like to see a full packet capture. And technically, the address was not 'harvested'. He gave it to them when he sent them packets. The story strikes me as very dramatic and over the top because of statements such as that.
Look in to what shodan is, its a service dedicated to portscanning the internet. With ipv4 you can easily scan every ip, with ipv6 you need some mechanism to discover addresses. This very much looks like they joined the ntp pool soley to harvest and portscan addresses.
"It takes less than five seconds for your address to be harvested and scanned. The entire scan takes less than one second and scans over 100 common TCP and UDP ports. "