The data stored with your protector is an encrypted version of your mnemonic, which is encrypted with a random 256bit key using AES. While the cyphertext is stored with your protectory, the key is again encrypted with your log-in credentials. The cyphertext of the random key is stored on our servers. The random key is discarded afterwards. All of these encryptions happen on your device. We will never see your mnemonic or random key.