jm Oݸù!DÌ fOn®-\Û¤±¡À±o¼ÊqbL©With mandatory I mean releasing an upgrade without backwards compatibility in case of bug. Miners and nodes with economical activity are incentivized to upgrade anyways.
https://whatsonchain.com/tx/355f54a0218e6813182590014222d3707216d2030f66d20301c203e1b9cdb8f1