I had a classic texted the person I was talking shit about a text about themself. When I unsent the message it displayed “you unsent a message” - does that mean it’s for sure gone from there phone, laptop, anything else??

I tired it out with a different person and theirs said “You unsent a message. ____ may still see the message on devices where the software hasn't been updated.”

Am I in the clear or is there anyway this person might still be able to see the text somehow???