'On PC, even if you have redeemed them, the ULC will no longer be available. 'The ULC will be disabled, meaning that you will no longer be able to unlock them,' Ubisoft's support post spotted by ResetEra states. Notably, this will include any 'ULC' (unlockable content) which you may have claimed.
Not all of these games have multiplayer, but all will be impacted in some way. Ubisoft doesn't have a firm date yet, though it has slapped a 1st June shutdown date for a number of other PC games: Assassin's Creed 2, Prince of Persia: Forgotten Sands, Far Cry 2, Anno 1404, Might & Magic - Clash of Heroes, Splinter Cell Conviction, The Settlers 7 and Might & Magic X - Legacy.
Ghost Recon Future Soldier, Rainbow Six Lockdown, Rainbow Six Vegas and Rainbow Six Vegas 2 will all be shuttered on PC, PlayStation and Xbox platforms at some point before the end of 2021. Ubisoft is pulling the plug on several older Tom Clancy games this year, meaning you'll no longer be able to play them online.