Sentencing ranged in five "bands" starting at between two years and four years six months jail for offences involving 5 to 250 grams, to life imprisonment for the most serious offending, involving more than 2kg.
Authorities had in 2005 not envisaged the much greater quantities which would be involved in meth supply a decade and more later, highlighted by the importing of over 500kg of meth and a seizure on Ninety Mile Beach, Northland in 2016.
One of the offenders was this year sentenced to 27 years' jail, although not regarded as the kingpin in a network said to be headed in Hong Kong, while in 2017 a man was sentenced to 28 years six months for offences which were linked to manufacture of meth but for which the total amount pinpointed was reported as "at least 6.5kg".
Some of the cases awaiting finalisation in Napier have been linked to or were uncovered in investigations surrounding the operations of dealer Shane Thompson, who last year in the Napier District Court was sentenced to 13 years' jail for his lead role in supplying at least 4.2kg of meth in Hawke's Bay.
Modifications now set by the Court of Appeal include greater consideration of the impact of addiction as a reason for offending, and while the amount will still be important, judges will have greater discretion in considering whether the individual is a kingpin making millions of dollars, or simply a street dealer.
The lowest band will now include community-based sentencing, with expectations there will be greater moves towards rehabilitation to help reduce demand.
The Law Society's Bar Association warns against the changes being seen as a softening of penalties in drug offending. James Rapley, QC, said the courts now have a greater range of flexibility to consider more rehabilitative sentences.
"The decision is about assessing the real culpability in each case and it reflects the need to find more effective ways of dealing with serious drug offending," he said.
Those at the "top end" of the manufacture and supply chains would still be dealt with "severely," he said.
The Hawke's Bay matters are currently scheduled to be before the court again next month.