Hey ,
This seems like this has more to do with the Timeline and the Lerp node than anything to do with the update to the networking system in UE4. Because of that, we do not believe that what you describing is a bug with the Unreal Engine.
If at anytime you have more evidence that your issue with the cards moving differently than you like is a bug with the Unreal Engine, please update this post and we can investigate further.
Thanks.