Don't believe any way to accurately know how many warrants have been exercised nor when the conversion will end in that they have been capped until November 17:
"The Toronto Stock Exchange ("TSX") has approved its previously announced amendment (the "Series B Warrant Amendment") to its outstanding Series B Common Share Purchase Warrants (the "Series B Warrants") agreed to with the holders of approximately 90% of the holders of the Series B Warrants intended to reduce the dilutive effect of the exercise of the Series B Warrants by establishing a cap on the number of shares issuable upon alternate net cashless exercise ("Net Cashless Exercise") of the Series B Warrants until the close of business on November 17, 2015"
May get an update from the company November 2 at the anticipated 3Q.
That the shareholders meeting is scheduled the day before November 17th is not random:
"QUEBEC CITY, Oct. 16, 2015 /CNW Telbec/ - Aeterna Zentaris Inc. (NASDAQ: AEZS) (TSX: AEZ) (the "Corporation") today announced that it has convened a special meeting of shareholders (the "Meeting") to be held on Monday, November 16, 2015, at 9:30 a.m. (Eastern time) for shareholders of record on October 14, 2015"
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