Section 3301. Applicability of this article to actions and matters occurring or arising before and after the effective date

Unless otherwise
  expressly provided, or unless the context otherwise requires:
    (a) the provisions of  this  article  shall  govern  and  control  the
  possession,  manufacture, dispensing, administering, and distribution of
  controlled substances with respect  to  any  matter,  act  or  omission,
  arising or occurring on or after the effective date hereof;
    (b)  the  provisions  of  this  article  do not apply to or govern any
  matter, act, or omission arising or occurring  prior  to  the  effective
  date  hereof.    Such  matters,  acts, or omissions must be governed and
  construed according to provisions of  law  existing  at  the  time  such
  matter,  act or omission arose or occurred in the same manner as if this
  article had not been enacted.