Yes SPPs allow a maximum of $15K regardless of how many shares...

Yes SPPs allow a maximum of $15K regardless of how many shares you own. In many cases I've seen 3 options available, $5K, $10K or $15K. If it is over-subscribed then the company pars back the amount for each investor at their own discretion.

But NightWatchman mentioned the word is it is a rights issue. In this case you can buy up to a proportion of the total shares you already hold. The company will announce what proportion that is but I imagine they'll allow most likely a 1 for 1 (I guess depending on the success of the sophi placement). You can also sell the rights to those shares for a period before they are listed.