DVD combos seem to be falling out of fashion these days in favor of digital download codes. All the 4K stuff I’ve seen for sale only includes a Blu-Ray as it is.
There’s also this possibility (this is what my TLJ and Solo 4K sets are):
Disc 1: 4K
Disc 2: Blu-ray
Disc 3: Blu-Ray bonus featuresCould easily just be SE in this case too.
If these rumors have any truth to them, I’m 95% sure this will be exactly it.