Interchange is the new framework to import files in UE. It uses pipelines to define how import will be processed and to expose the options for that import.
When you import a texture (or an asset) the type of pipelines and the options that were used are stored on the asset. So that when you reimport the editor remembers what pipeline/options you used.
There is no reason why this property becomes empty, especially since you are using the default pipeline. I will ask Dev if that rings a bell to him.
Did you restart engine between a successful import and a failed reimport?