One of the earlier and more prominent ones came from Avixes, or Mohamad Amirul Mohamad. He leads the Southeast Asian Rainbow 6 Siege team, under Lese Esports. Using public DNS does not solve the issue either. According to a followup by the official unifi Twitter account, it looks like there were more who have faced this issue.
Kenapa @helpmeunifi nak kena block @Ubisoft punya connection? Kami atlet esukan wakil negara utk @R6esports @Rainbow6Game macam mana nak training/main kalau tak boleh nak connect langsung? — Amirul 🇲🇾 (@Avixes) February 7, 2020 This connection issue is also one that only affects unifi subscribers. According to WTM Today, Mohamad Amirul also says that other players subscribed to Maxis or Time were not affected, and are able to continue playing Rainbow Six Siege. As for the ISP’s response to the matter, it would appear that it is not restricting access to the server. At least, not intentionally. The ISP is currently investigating the matter with Ubisoft.
— unifi (@unifi) February 8, 2020 For now, it’s unclear what’s the cause behind the entire thing. For what it’s worth, unifi’s clarification at least serves as an assurance that the blocked connection to Ubisoft servers were not supposed to happen. (Source: @Avixes, unifi / Twitter, WTM Today)