If we were to go with that proposal, could teck then say that they will not back in?

Teck has one opportunity to make one decision on how much they will earn back. Once their decision is made they are locked into a contract.

That is why it makes sense for Teck to try and buy out the remaining 25% before they tell the world what percentage they will earn-back. It makes sense for them to buy out Schaft Creek and other properties from within the Agreement, and anything outside they want, before they let anyone else know how interested they are. Once Teck declares their interest then the rest of the world knows what exactly is for sale and who the partner will be and how much money Teck will have to invest. It would be crazy, imo, for Teck to reveal that information before attempting to buy us out if they want to own any portion of this property. Even if they only want 20% it makes sense to offer us a buyout and then split the property themselves by selling off whatever they don't want to another partner.