A little further...
Comments are taken on the 'new' NEC for a period of time (45-90 days)
Comments are reviewed, rejected, or accepted as amendments.
A period of time passes, and the 'new' NEC is adopted, with amendments, and entered into the State Register.
A 'drop dead' date (usually 3-6 months) is set, and on that date the 'new; NEC is mandatory.
Yes, there is a minor rush IF there are major changes.
In that confusion, ECs are required to do the 9 hour code change CEUs on the 'new' code. Still working under the 'current' code, and on 'Rehab' work, using one code back.