The Permanent Resize feature clearly states that the CPU, RAM and disk will all be resized. I resized from 30GB to 40GB and a df -h (FreeBSD droplet) command showed the same. What gives???
freebsd@ivts-fbsd-db1:~ % df -h
Filesystem Size Used Avail Capacity Mounted on
/dev/gpt/rootfs 28G 3.7G 22G 14% /
devfs 1.0K 1.0K 0B 100% /dev
https://www.freebsd.org/doc/handbook/disks-growing.html
This tutorial should be of some help, but it does suggest that you will need to boot a rescue environment and resize the filesystems while they're unmounted.
If this were a Linux droplet with Ext4 partition, you would still need to resize2fs it from within the droplet, lest it report your originally provisioned capacity.
I had snapshots taken prior to the resize. I destroyed my droplets, then created new (bigger) one from the snapshot. That worked.
Poor form Digital Ocean, this was not documented about the permanent resize feature. And because of destroying my droplets, I could not keep the same IPs, which has caused havoc across the board.