"OK, we won't do retroactivity."
https://www.salestaxinstitute.com/resources/hawaii-enacts-economic-nexus-legislation
http://files.hawaii.gov/tax/news/announce/ann18-10_amended.pdf
http://report.saltcpa.com/2018/07/hawaii-enexus-retroactive-enforcement-date-revised-to-july-1-2018-with-updated-announcement-no-2018-10-dated-july-10-2018/