AFAIK they're not planning to announce minor things like oil on...

AFAIK they're not planning to announce minor things like oil on the shakers as we know oil is present. I'm not sure if this means that all of the targets will be drilled before reporting any success (is there even a way to avoid making the discovery until all targets are drilled?)

It'll be nice to have a bit of a quiet period while they drill.

Constant "news" flow won't really impact the result that I'm interested in (either a commercial discovery or a duster), so I'm happy for IVZ to do their thing and not need to get distracted by marketing their status updates.

While it'd be nice to get a kick (and get the news of a commercial discovery early as a result), announcing things every 20m is likely to damage the final share price more (particularly if the top few targets are unsuccessful) -- IMO the market still doesn't properly understand what the co is doing and sitting on, and a single missed target would likely cause unnecessary panic.