[Interest] What happened to 5.5.1 branch?

[Jason H]

Git issues:
0. I'm using Atlassian's Source Tree.
1. I checked out the 5.5.1, and created a branch called osx_recording_params. SourceTree shows me the [osx_recording_params] in the "SourceTree" window.
2. Things were fine until 5.6 branch happened.  Now, the list of pre-5.6 branches is gone. 
$ git branch
* (HEAD detached from c595fc7) # <- this was the 5.5.1 commit of qtmultimedia that I checked out.
  5.6