Opening and Closing Auction Explained, page-9

I have a few theories for why the long halt rather than just dropping the announcement.
A) The results weren't quite ready for release (still required a few days to reconcile and prepare into announcement form), but the company seeing the volitility on Tuesday, and knowing results were close, requested the halt so investers, rather that trade shares in or out based on the overall market, could wait and base their trades on truly important information. Drill results..
B) Drill results weren't quite ready,, but with more people in the loop regarding the results (lab? Etc), they put the halt on to prevent any leaks while results are prepared. (The perfect use of a trading halt)
C) Drill results were close (or not maybe that close), but seeing the volitility Tuesday, didn't want the SP all over the place and maybe back down under 2.0, so they quickly checked that they would have enough results by Monday for an announcement,,,, called the halt,, and scrambled all hands to get an announcement ready with all the results they have so far...
That's one for the conspiracy theorists..

All plausible reasons, maybe a varying mixure of all three.. Regardless now, results are coming, and they'll either confirm a winner,,, or let us know ADV still have work to do to prove economic viability.. most have already placed their wager of what which it will be..

Also good work explaining how the auctions work... It's kind of a simple concept, but almost impossible to explain simply and know somone will understand the explation..