Adding passphrase (BIP39 passphrase) to a BIP39 seed phrase will produce a different binary seed, thus different set of keys.
So, by using a temporary passphrase, you'll have access to a different wallet that can only be accessed by typing the temporary passphrase.
Think of it as a separate "hidden wallet" in your Ledger Nano.
Alright, I think I got it but the word "temporary" is really confusing me.
So, the temporary passphrase option is not for long term hodling, right?