spp when was last day to buy

JAK announced a share purchase plan at 15 cents for all eligible shareholders who are registered at 5pm WST on 20th October.

In order to be eligible, does this mean you would have had to purchase them on or before 17 October, so that with T+3 you would be registered by 20th October?

If it does, then it means that everyone who bought on the announcement on 18th October will not be eligible. Given that the share price was around 11 cents before the announcement, that would mean that the investors who took the placement at 15 would have either had advance news of the announcement, or would have taken the shares above market.

Either way, it would seem that (if my dates are correct) the shareholders who bought in on the announcement are missing out on the SPP, and are thus (on current prices) getting the rough end of the pineapple.

Can anyone clarify this for me.