If two of the world's largest DDoS mitigation companies are having trouble, then you can get a sense of the scale of the attack and their sophistication.Source of the cyber attacks - (Microsoft, Google, facebook, Amazon, Palantir and ASN[3 Letter Agency code) link from reddit : https://www.reddit.com/r/ProtonMail/comments/8uu9t7/update_regarding_the_ddos_situation/
Corporation Warfare-Protonmail cyberattack sponsored by states and corporations | Heykuki News