This referendum aims to cancel referendum #106, which upgrades Kusama to runtime 9380.
A followup referendum will be proposed later to enact this runtime upgrade at a later date.
Kusama runtime 9380 contains XCM v3 which is major breaking change. We have confirmed it is not compatible with current version of Karura and expect to upgrade Karura next week to address the compatibility issue. It also removes XCM v0 and v1 support which is the only option exposed from xcmPallet. This means all the wallets and dApps are required add additional logic to detect the new version to be compatible. I don't know about others but Karura Bridge UI and Polkawallet are expected to complete the upgrade next week. However iOS release will likely take more time due to App Store review.
The Polkadot v0.9.38 release is created less than a week ago and it could be enacted in another week. This means everyone have less than 2 weeks to develop & test & release in order to compatible with the new version. While this is not an unreasonable timeframe, it unnecessarily add pressures to all the parachain and tooling teams.
Also I don't think we have any urgency on this release anyway so it should be safe to delay it until the ecosystem is ready.
This proposal aims to cancel referendum 106, to then be submitted taking a particular block number for execution. To note, referendum 106 aims to upgrade Kusama to runtime v9380, and contains XCM v3: which is major breaking change. The Karura team has requested more time to finalise testing. Please make sure to vote at your convenience!