I am sceptical by nature and for those reasons I take a brief look at what is being posted by who before following my gut feeling. As it stands, I refuse to believe what you have stated about discovering some Bitcoins in a wallet you thought was empty. This sounds to be more fiction than fact.
Furthermore, using OpSec as a convenient deflection tool might make some believe your story but I do not.
I have a wallet which I thought was empty for months. I just recently logged in to that wallet and find out that it has still some Bitcoins.
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Only because of OpSec I am not sharing screenshot of my wallet along with other details. Hope it's not required as I want to highlight the point related to Bitcoin gain in value and advantage of forgetting the Bitcoins you have (without losing the keys).