Thanks for your response though I still think my reasoning is...

Thanks for your response though I still think my reasoning is sound. My thinking relates to the EML releases at the time.
They requested a trading halt prior to the opening of trade on the 17th of May (Monday).
On the 19th of May prior to the halt being lifted they notified the market of the regulatory issue and disclosed that they had received the letter on the preceding Friday 14th (time not given). In response to an ASX price decline query on 25th May they clarified that the letter was received on Thursday 11.12 pm (all times here are local Aussie time) and the letter was received in Australia at 12.37 am (Friday) and a meeting arranged at 0630 Friday morning. They then received legal advice (in Ireland) by Friday evening and a decision was made to call a trading halt prior to the trade on Monday.
In short it appears to me that the ASX agreed to the trading halt when requested by EML but the request was not made until a full days trade had occurred after EML received the letter. Clearly EML did not regard the letter as routine and on disclosure of the letter they withdrew their profit guidance. I do think that people who bought shares on the Friday and then sold them at a loss on hearing of the change in circumstance have a case that they would not have bought the shares and suffered a loss had they known of the issue. I am not saying it’s a slam dunk especially in relation to the time differential between Australia and Ireland and as I have mentioned it’s limited to one days trading as far as I can see. If anyone thinks there are more significant exposure legally I would appreciate your views.