Instanced rendering breaking translucency for instanced meshes?

Currently i am working on a project where we have several “holographic” objects shown to the player while he’s in VR.

However after upgrading to 4.11 and enabling Instanced rendering we quickly noticed that all our translucent objects were displaying fine for one eye.
But for the other view the rendering appeared glitched and broken.

We pinpointed that this only seems to affect “instanced” static meshes and are now trying to replace all the “instanced” versions with regular static meshes.

Is this a known bug? if so, Are there plans to fix this bug?
And is there a way to work around it without having to disable instanced rendering (or replacing all instanced meshes with regular meshes)?

Here is a crop of the glitch happening:

The right eye you see the hologram match the floor plane perfectly, in the left eye you see it getting cut off at weird angles.

EDIT: This also seems to influence “masked” and “additive” shaders

i am also having transparency issues in 4.11.1 Massive framerate hits whenever transparency is drawn. This was not an issue in 4.9 [same assets]