Re Commsec's "no trades shown" for ~15 minutes today : I think...

Re Commsec's "no trades shown" for ~15 minutes today :

I think you'll find whenever any Company makes any ANN - other than a Trading Halt - trades do not executed for about 15 minutes - from the start time of the ANN.
MAY'S ANN was @10.52am hence fitting in with my suggestion.
Check it out for a stock in which you see an ANN, then go to your broker's Market Depth / Course of Sales page and then note the gap period between the last trade pre the ANN and the first trade after the ANN.