Service Bus is only needed as a separate package if you don't want to use Connect ID SDKs. Otherwise, download the relevant package from "Connect ID SDKs" folder, they all contain Service Bus library.
Release notes of the Service Bus are part of release notes of the main package and can be found here.
Download / Latest
Download / 2020-10-29 (Sprint 129)
Download / 2020-04-30 (Sprint 117)
Download / 2018-10-19 (Sprint 77)
Download / 2018-9-27 (Sprint 75)
Download / 2018-01-23 (Sprint 57)
Download / 2017-12-07 (Sprint 54)
Download / 2017-03-14 (Sprint 35)
Download / 2016-12-22