I have one student who downloaded a .ai file from a Google drive and he probably pushed it to the Creative Cloud workflow. It converted to a .aic and, in the process, the layer structure and the object structure changed from what was in the original file. Instead there is nothing more than clipping masks and objects. It is reminiscent of version incompatibilities.
I have attached screen captures of the original and the converted file below:
Note the second converted version is clipping masks.