From the press release:

The special warrants will be exercisable at any time following the closing date and shall be deemed automatically exercised, if not already exercised by their holders, on the date which is the earlier of (i) the third business day after the date a receipt is issued, in respect of a final prospectus filed in certain Canadian jurisdictions to qualify the distribution of the common shares and purchase warrants forming the units to be issued upon exercise, or deemed exercise, of the special warrants, and (ii) the date which is four months and one day following the closing date.