Ann: White Rock discusses Current Exploration at Last Chance, page-7

They can accept over subscriptions. I don't think they specify any maximum to the over subscriptions. So potentially I think they could accept everything.
The dilution aspect is complicated as far as I can see.
Without over subscription holders at record date are being diluted by roughly 50% give or take IMO . Over subscriptions if accepted will lessen dilution for them as a whole if they subscribe. For people who bought after record date over subscriptions if accepted will dilute them more than if they aren't. IMO.