/vt/ - Virtual Youtubers

Ever since the Rushia incident there is a high chance Cover pays more attention to the accounts of holos and check up on what they do there. After all that was when, after Rushia's GTA yab, they decided to take a closer look at what she has been doing on her Rushia accounts.

The wording suggests this wasn't a singular offense, so if she leaked info (maybe by just being too naive and dumb, not even malicious) she probably did so multiple times over a span of weeks at least. Whether the recent months of VCR and constant contact to non-holos are somehow connected to all of that is hard to say but possible.
Keep in mind the JP statement says Mel herself agreed with the termination, so it's very unlikely that it isn't deserved.