Fdbcli configure command

From the documentation on fdbcli for 7.2, I can see there is a configure command under fdbcli to enable “encryption_at_rest_mode=aes_256_ctr”
So, is this feature is now officially in 7.2.x (x>=0)?
A second question will be, if I have an existing database, can I enable this without recreating the database or do a backup/restore?