Ann: Annual Report to shareholders, page-52

By my calculations if they want to produce 12000t cobalt sulphate theres enough for about 16 years using the entire measured/indicated resource.
I calculated about 45000t contained cobalt using indicated/measured tonnages and used a 90% recovery rate! (I appreciate recovery may be higher but will see what dfs shows)

45000 tonnes cobalt at 0.07%
90% recovery is about
40000t contained cobalt give or take
so about 16 years producing 2500t contained cobalt. Also processing the entire resource

I appreciate my calcs may be wrong and will happily look at yours and compare. You know a lot more about this than i do.