I am holding my tokens in my wallet more than one year. It is not a problem, just do not forget your private keys. I am not send the tokens to the exchange markets because if i send, i can sell them but i do not want it. Price is depend the market prices.
The point is as long as you have a backup of your wallet, then it wouldn't have any trouble. And also be careful with tricks used by hackers, because you're the one that responsible to secure your wallet. My advice is do not hold token too long, because that is not necessarily valuable forever, unlike bitcoin.