on my trezor i have stored my BTC for years now, I STILL HAVE ACCESS TO MY BTC AND MY TREZOR WALLET THANK GOD, but i wrote the 23 word (i think) passphrase on a paper and stored that paper in a safe place, but recently i F moved to a different country, i took those documents with me but i think i lost them !
You should keep passphrase
separately from your 24 mnemonic words, but it is good thing to have several passphrase copies stored in different locations, and please don't trust flimsy human memory to remember anything.
Safest thing would be to send your coins to different wallet you control, than reset you trezor wallet, generate totally new seed words and add new secure passphrase.
am worried they might fall to the wrong hands ! so i need to change the passphrases which i no longer remember, how to do that ??...
Passphrase is like a added salt and once you mix it with your seed words you can't change it or remove it anymore, but you can create multiple passphrases just make sure you pick one that is secure mix of several words and numbers.