System Information
Operating system: Linux Mint 19 Tara
Graphics card: Geforce GT 630

Blender Version
Broken:
2.80 (sub 35), branch: blender2.8, commit date: 2018-12-08 17:06, hash: e79bb957fc3

Short description of error
Bendy bone duplicate got wrong handles

Exact steps for others to reproduce the error
1.: Create a bendy bone system:
(subdivide bone in 3 parts, unparent 3. bone, "stretch to"-constraint 2. to 3. bone, set for 2. bone start handle (bone, type: "Automatic") and end handle (bone.001, type: "Absolute")
2.: Select the bone chain in edit mode and copy it. One would expect creation of bendy bone.004 with start handle .003 and end handle.005, but Blender mixes up the handles and bendy bones of both chains. So the first bendy bone stretches to the end handle of the second and vice versa.