Quote from patch note: "Starting with Season 9, players will be able to complete the Sanctuary’s Most Wanted objective in the Season Journey across multiple games"
# 1 Jan 6, 2017
# 8 Jan 6, 201701/05/2017 11:46 PMPosted by yessquireI think it means that you no longer have to complete all 5 Bounty Acts without leaving or being DC.
Just jumping in to clarify that this is correct.
While you still need to complete a full set of Bounties and collect the Horadric Cache in each act, you won't have to do all Acts I-V all at once. For example, you could do two in one game, one in another, and the final two in another. Hope that helps!