The not-blocked election property will be deprecated as part of T268800: SecurePoll should differentiate partial blocks from full blocks.
The old property will be replaced with properties that distinguish between partial blocks and sitewide blocks.
For now, we're still handling this deprecated property, but we should remove it and bump the SecurePoll version number to 3.0.0 to indicate the breaking change, at a time when no polls are running in production.