You are correct . An public announcement must follow the rules...

You are correct . An public announcement must follow the rules on timely disclosure of price sensitive information .... it cannot be held back to coincide with a particular investor presentation (unless, as in the LVAD trial results, you have no control over the timing of disclosure of the clinical trial results). I believe that this conference is regular event which MSB has presented at in the past. By making these announcements, they allow institutional investors who wish to follow the Company, to either attend in person , or register on the remote access service to watch the video conference .
If you look at the historic reporting schedule of this company, you will note that last year the 6-K quarterly ASX update occurred on the 31st May 2018 after the 4C was announced on the 30th April 2018. I am sure that the normal audit is underway right now and investors are aware that Mesoblast will consider itself in a “restricted period” during this time. For this reason I doubt if the presentational material will change for this event.
That does not mean to say that nothing new will emerge. A good analyst, who has followed the Company for a period of time , will probably notice if there is a change of emphasis on particular points of strategy, etc.,
As a few others have pointed out in recent posts , Mesoblast is awaiting the standard period , of between 30 to 60 days, for the minutes of the pre BLA meeting to be prepared and received. That meeting was originally scheduled in late March, although we received notification of its occurrence on April 16th, so it was delayed a few weeks following the US Government shutdown. Either way, it is a racing certainty that we should expect MSB to file its first module submission in the very near future.... so everyone relax and take a deep breath.
Investors should note that prophecies of an endless wait and death by boredom ,could not be further from the truth. MSB management have continually said that a global deal would be data dependent . They have also suggested that confirmatory trials would draw upon results from trials in China, Europe and the US, so I would suspect that securing a European pharma ( or one with a presence there) must be high on a long list of priorities.
In June, MSB is scheduled to meet the FDA, to discuss the BLA submission for its LVAD treatment....any fast tracking with regard to this treatment would be especially well received by the market in my opinion.
The elephant in the room is when then CHF trial becomes unblinded following 540 Major Adverse Cardiac Events. SI has referred in the last presentation to a “J curve “ of MACE events to occur in the next 6 months if results from the previous clinical trials are observed. Strap yourselves in for the ride... with your legs firmly crossed.