Not sure if related to Vesper's suspension, but at 2:39:56 in Magni's latest Sonic Frontier's stream Vesper types "?!?" in chat. Magni says he forgot to do something for somebody else. He ends the stream shortly after.
From what I can tell less than 30 minutes passed from the ending of the stream until the announcement on Cover's twitter account. Vesper was using his youtube account at least 30 minutes prior to the announcement. He also posted one message earlier in chat.
edit: wait, now i'm seeing some say that Vesper's "?!?" comment happened almost at the same time as the announcement. I only have an estimate of the stream's end time. Does anyone know the exact time it ended? Would this mean vesper wasn't told about his suspension until the announcment?
From this, as a person with no clue as to what they're talking about, the decision to suspend him appears to have been a kneejerk one and might be to assess Vesper's situation.
Timestamped magni stream. Begins after the 2:39:56 mark and skips to when Vesper's comment appears on stream.
Not sure it's related myself, but since you asked. According to Holodex Magni's stream started at 21:02 PST. That places Vesper's comment at 23:41 and the stream ending at 23:44. The Japanese announcement was posted at 00:20 PST. In any case Vesper was using his Youtube account less than an hour before the announcement.