How to resolve the Abnormal nodes issue in my model?

I am encountering a problem here with abnormal nodes. I am not sure what went wrong with the boundary conditions.
Do find my models here with the construction sequence of the 3-span integral concrete box girder with external span modelled along.

I reviewed the model. 

Bearings boundary group are provided for different beam end releases. They all are activated in CS2. The corresponding girder are activated in different construction stages. 

Now, when the beam end releases are provided, they are giving warning regarding the structure stability which can be ignored if the behaviour obtained is as expected.

Secondly, try providing the beam end releases to the other end of beam i.e the end which is connecting to the superstructure/girder.

The model file has been attached in which beam end releases are provided to different bearing groups and are activated in different construction stages to reduce the number of warning as shown below.

Below image shows different boundary groups activated at different construction stages.