i created a wallet form web wallet
and an keeping safe 12 words and a bitcoin address public key and private key
and that single public address has all bitcoin now i m never going to use that wallet as i m going to hold bitcoin till 2025
my question is what if community tries to upgrade bitcoin and is it possible that that private key wont work because of upgrade.....as i see back in 2011 people use to keep bitcoins on a hard drive ....
i just want to know would i be able to recover my funds as long a i have my private key whatever happens to technology....
All of the above advice covers everything you need to know. The best thing to do is to keep it on an external drive or flash disk, write down your seed words on a piece of paper somewhere, and never lose that disk. Then it'll remain safe.
I'd recommend updating your wallet whenever it comes out just to keep up to date. I usually don't update until the release is a few months old to avoid bugs, just in case.
Also, it's not the best idea to set a sell date in terms of a specific year or time because there might be some changes in the market before then that could be more important. Be flexible and willing to sell if market conditions call for it before your expiry date.