Don't destroy your droplet then? Digital Ocean supports reinstalling VMs in place without destroying the VM. Floating IPs for a mailserver (esp. outbound) sound

Don't destroy your droplet then? Digital Ocean supports reinstalling VMs in place without destroying the VM. Floating IPs for a mailserver (esp. outbound) sounds a bit silly, mail infrastructure is more fault tolerant than other systems, to the point that a minute or two of downtime is far from the end of the world.