[RobAley]

You keep it until x days/weeks after the servers are deactivated. Where the emails are going unnoticed, the servers getting cut off usually is noticed straight away. The story here appears to be that the backups were deleted at the same time as the servers. For the relatively small cost of those who don't subsequently pay up, you get a lot of goodwill from the majority who just messed up.

[Tassels]

When an account on DO is late with a payment, you go through three stages: hold, suspension, termination.

The hold happens right away and prevents you from creating new billable resources.

Then a suspension happens several weeks later, which powers off your servers.

You don’t get terminated until a couple weeks after that, at which point the data is irretrievable.

The time between each stage can vary depending on how long you’ve been a customer or what your monthly payments in the past have been, but that’s the gist of it.

[KajMagnus]

It'd be nice if one could pay a bit more in advance, so one's data stayed some weeks or months longer than default, after the servers got powered off. — As an extra safety net, if the credit card expires when one is in bed for a month with a broken leg or some bad luck thing like that.