To facilitate the upgrade to 2.1, the core developers are working on an on-chain smart contract that, once ready, will allow Stackers and miners to vote on when (or if) the 2.1 upgrade should take place. When it is ready, a 2.0 point-release will be made that rigs the 2.0 node to cease processing Bitcoin blocks at a block height determined by this smart contract. In doing so, the Stacks 2.0 network will stall out once there is enough support for 2.1 and the 2.1 network will resume processing blocks from when the 2.0 network left off. Note that the Stacks 2.1 upgrade follows the standard SIPs process
; this vote will essentially be to either accept or reject that SIP.
The specific process by which the community can vote on this and future upgrades is being discussed here
. The goal has always been to enter a state where the community can more easily determine the content and timing of major upgrades such as this, so this process prioritizes the work to enable that type of voting before the Stacks 2.1 upgrade as opposed to after it.
You can sign up below to get an email when more details about voting are available or you can track the Github issue here
until a Stacks 2.1 SIP emerges.