Ann: 2019 CY Guidance, page-15

IMO, the reason that Mr Market has not put upward  buying pressure on the share is because the company has not yet announced the $s/ton it actually received for both shipments and he suspects that the reason for this  is that it may have been under the $580/ton* predicred
above. If there is an off take price agreement/ formula for calculating price for all the HMC to the Chinese customer , then the company should announce that. IMO, a spot sale would also verify pricing.
This info will be available in the Mar Qtr because the revenue & tonnages sold will have to be disclosed and the SP should move along, IMO.

* The CY 2019 guidance gives sales volume: 220-240K ton Average 230K ton
& Revenue $125mil-$142 mil Average $133.5 mil which is $580/ton
IMO, Mr Market expected mid 6s.

The above Ann also lifts the COP from $361 mid Feb Ann. to $402.50 in the CY 2019 guidance 2 weeks later. 

Even with these variances, the SP should have advanced beyond 20c , IMO because of increased grade/production volume.