Stocks remained adequate and the previously flagged earlier planned maintenance for the coal handling and preparation plant was underway, the company said in operations update.

“With the quarter and financial year drawing to a close, the company remains on track for a strong June quarter and will marginally exceed prior guidance for run-of-mine and product coal produced,” Stanmore said.

“This performance, coupled with the higher than anticipated June quarter benchmark settlement of US$126/t for semisoft coking coal, has Stanmore in a strong position to finish the year and commence FY18.” The prior June quarter forecast sales of 305,000t has been reduced to 265,000t with a thermal cargo, which is fully assembled at the mine, deferred to early July due to short-term rail constraints.