Reassign a floating IP from one droplet to another:

doex floating_ip.reassign <old_droplet_name> <new_droplet_name>

Or, by tag:

doex floating_ip.id <old_droplet_tag> <new_droplet_tag> --tag

If by tag, it will grab the latest.

For example:

doex floating_ip.reassign myapp01 myapp02

If you have a specific config file, mix help doex.config then add it as an environment variable:

DOEX_CONFIG=/tmp/my.doex doex floating_ip.reassign myapp01 myapp02