Stonghold Digital (SDIG) closed on the seventh and final tranche of bitcoin miner deliveries to NYDIG that had served as collateral for financing agreements with NYDIG, the miner said in a Tuesday press release.This final tranche allowed for the cancellation of $2.1 million in debt. In all, since mid-August Stronghold has returned about 26,200 miners to NYDIG in return for the extinguishment of $67.4 million in debt.