EasyUO reads data from memory. Each time you change the code structure it reallocate the position where in memory specific data will be stored.
For them they may only increase the Version-Number (since Client is an Container wich only react on packets and show graphics) but for euo it means the variables (stats, mobiles, items) are stored at a different place.
So each time uo updates their client version, we need to upgrade the offset to read the memory data.
B/S could now very easy break easyuo, they could add more packets , different structure and woosh, the memory data for finding offsets will be different and the current method wont work anymore until someone upgrades code for the new structure