Changing Bend type causes eccentric reduction to rotate

[mcbubble]

Revit has this strange behaviour. When I replace a bend in my piping system with a different type the connected eccentric reduction just gets changed, rotated by 180°. The new type is basically the same family symbol with few properties more. Why does this happen? Is it a bug in Revit?

It happens both when I do it manually via the Properties Dialog, or via the API "ChangeTypeId" function. The entire pipe system in the project has four such bends with reductions, but it only happens with one of them.

What I also thried is to change switch the eccentricity before changing the type. It still changes it to the opposite site it had before updating the bend.
Any ideas anyone? 

[fabiosato]

Hello,

Usually, leaving a small segment of pipe, a few millimeters long is enough, may avoid your problem.

[mcbubble]

The problem is I am programming a tool to update families via the Revit API, I cannot tell users how to build their piping systems. To make sure the problem is not a programming error on my side, I did the same manually. There is obviously a bug in Revit, so I was hoping someone knows a workaround or trick to stop this erratic behavior, without having to change the system.