It's 400 clients, not all their user base. They can handle the lost income from a small slice of their customers for one month.

And if they can't sustain that, then it's even more imperative that those customers migrate away.

Atlassian had almost a billion in free cashflow last year and over a billion in cash. I think they should cover the whole year for these customers.

Fastmail gave 1 month free service to about 2/3 of our customers after a major disk failure that led to about a week of downtime for them as we recovered from backups in... 2005ish I think. Long time ago - it was a pretty major hit and the wave in income is still visible all these years later as a lean month where there's no renewals from that batch! Definitely the right thing to do though.

400 clients, but how much of their revenue? Were they all small clients? Not to mention longer tail effects of people moving away to competitors even if they werent directly affected?