According to asx rule 7.1, the relevant period is the 12 months before the issue. They used up their original 15% allocation BUT they can still allocate 15% of the number of RIGHTS ISSUE shares as they are an exemption to the rule.
15% of 64,734,863 = 9.71 million shares.
= They can allocate 9.71 million shares without s/h approval.