Cokal said the project's haul road continued to be upgraded and the Krajan Jetty preparation was nearing completion.
"Development continues to advance rapidly, with first saleable coking coal production on-track for September 2022," it said.
Cokal appointed CBQ as an additional mining contractor to provide mining services and overburden removal in August.
CBQ, established in 2011, has operated in various overburden removal projects in Java and East Kalimantan.
Cokal chairman Domenic Martino said the existing mining services contract with HPU remained in place.
"Cokal's intention is to utilise HPU as a mining services provider subsequent to the initial commencement of production at BBM," he said.
"At this time, HPU would supplement the ongoing contract mining services provided by CBQ."
Martino said the appointment of CBQ would help reduce costs, increase annual production potential, and Cokal undertaking its own coal mining operations.