There doesn't seem to be an ETA, but a resp. enhancement request has recently been accepted by the Bitbucket team, and it gathered a notable number of votes already - you might want to watch and vote for the issue as well to guide Atlassian's roadmap in this regard:
As a project manager, I have discovered that different developers want to bring their previous branching method with them when they join the team. Some developers are used to performing individual wo...
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