Might be a coordinated attack against the network providers that MS uses?
MS: Our investigation determined that one of our network connections to a third-party ISP was not taking traffic. We've diverted traffic to alternate channels to expedite recovery. For more information please follow MO273940 in the admin center.
Other source: This is related to a BGP hijack of at least 87.128.0.0/10 belonging to Deutsche Telekom (AS3320) hijacked by AS212416 (Proximity, Bulgaria) passing through AS57344 (Telehouse EAD, Bulgaria) starting at 0633 UTC today.
Your other source quote is a direct copy of a tweet from 2021: https://x.com/rrbone_net/status/1420656486573805570
You don't think if it was a DDoS attack they would've identified that by now?
This is also not the normal type DDOS. They are not being spammed. Instead the connection to the ISP is being disrupted.
This is from MS themselves:
https://x.com/MSFT365Status/status/2121079061774491735
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