The difference between the two is the first says 'material...

The difference between the two is the first says 'material respects' & the second says 'completion'.
ie they've done the material aspects of the DD now but still need to complete the immaterial aspects before making an offer.

I know it sounds petty but I suspect they're just following due process.
As I posted before I think they're closer to making an offer than they were & I'm surprised the market wasn't more positive to the release.