I see between now and the end of November (subject to timing) they can purchase approx. 1.7m and then are stuck until Feb. However, 457k warrant expiry is on Jan 10, which is exempt from 5% as it's a shareholder right. The same goes for their 2023 1.2m allotment. So they could continue to chip away until Feb via warrant exercise if I understand correctly.
It looks like they're sending Rio a notice... we're here, we'll be here, DON'T F$%& WITH US!