title: "Fix multi-collator parachain transition to async backing"

doc:
  - audience: Node Operator
    description: |
      The dynamic Aura slot duration, introduced in PR#3211, didn't take the block import pipeline
      into account. The result was the parachain backed by multiple collators not being able to
      keep producing blocks after its runtime was upgraded to support async backing, requiring to
      restart all the collator nodes. This change fixes the issue, introducing the dynamic Aura
      slot duration into the block import pipeline.

crates:
  - name: "polkadot-parachain-bin"