Hotstuff is an SMR (blockchain) protocol achieving O(n) communication complexity within views. Unfortunately, Hotstuff leaves open the matter as to how to efficiently achieve view synchronisation. In these notes, which are joint with Ittai Abraham, I describe a deterministic protocol (modulo establishing a PKI) with at most 2n messages of constant size sent per view change. This improves on the state of the art, which was O(n) expected communication complexity per view change. We’ll be posting a paper version soon.