"Active" with those systems just means the encryption key is now user-supplied instead of being stored on the controller/drive. The actual encryption is always active; which makes sense, if anything it means you have one less configuration to test.
If I learned one thing about SSD firmwares/controllers it's to be sure of nothing. Especially when the market is flooded with cheap controllers that can barely keep up with line speeds I'm very much doubtful that they're unconditionally encrypting at rest data.
