This proposal aims to upgrade remaining system chains to v1.6.1, except for Asset Hub which was not changed in v1.6.1, and so will be upgraded to v1.6.0.

In addition this proposal also includes a call to Fix XCM version subscriptions for some system chains

These are being bundled into one proposal to avoid back-to-back whitelisted referenda. The Fellowship is also voting in parallel to whitelist the proposal hash. If approved, it is scheduled to enact at block 27476030.