It long time I have not watched topic.So many rebranding. So,If i have a little Xtri on my old wallet Lithium 3.1.0 ,what i need to do to save my coins ?
Your coins are always safe, they are unless the network is 51% attacked and the blocks where your transations were are re-written.
You have to update your wallet to be able to use your coins. Remember to save your seed and / or your private keys before updating.