Ann: OZL: OZ Minerals' Option to Acquire Kalkaroo Copper Project, page-63

From my quick read
Didnt notice anything about 30% retain, 30% was mentioned in reference to uplift in resource, additional contingent consideration of $65M
Kalkaroo Pastoral and Station is not included
1/2 of the $1m per month needs to be spent on drilling etc, the other half to keep the show on the road

In addition, the agreement provides a deferred contingent consideration of$65 million, upon a 30% uplift in Kalkaroo’s Measured and Indicated Resource estimate

The sale of the Kalkaroo Station Pastoral Lease is not included in theProposed Transaction.(b) Kalkaroo Pastoral Company will grant OZE access to the Kalkaroo StationPastoral Lease under the Access and Compensation Agreement which willcontain the following provisions:

OZ Minerals will pay Havilah $1 million per month during the Option andAlliance Period, with 50 per cent of the payments directed towards Havilah identifying and advancingnearby exploration opportunities