The documentation doesn't specify an exact deadline for migrating from Prefect 2 to 3. However, it suggests that the transition to Prefect 3.0 should be relatively seamless for most users, with compatibility maintained for most Prefect 2.0 workflows. You can find more details and guidance on the upgrade process in the
Prefect 3.0 upgrade documentation.
If you are considering the migration, it would be prudent to start planning and testing the transition sooner rather than later to ensure a smooth upgrade.