Final Targeting Strategy for the Sloan Digital Sky Survey IV Apache Point Observatory Galactic Evolution Experiment 2 North Survey

APOGEE-2 is a dual-hemisphere, near-infrared (NIR), spectroscopic survey with the goal of producing chemo-dynamical mapping Milky Way Galaxy. The targeting for complex and has evolved time. In this paper, we present updates additions to initial strategy APOGEE-2N presented in Zasowski et al. (2017). These modifications come two implementation modes: (i) "Ancillary Science Programs" competitively awarded SDSS-IV PIs through proposal calls 2015 2017 pursuit new scientific avenues outside main survey, (ii) an effective 1.5-year expansion known as Bright Time Extension, made possible accrued efficiency gains over first years project. For 23 distinct ancillary programs, provide descriptions aims, target selection, how identify these targets within sample. Extension permitted changes strategy, inclusion programs response discoveries or exploit major datasets not available at outset design, expansions existing enhance their success reach. After describing motivations, implementation, assessment also leave summary lessons learned from nearly decade APOGEE-1 operations. A companion Santana (submitted), provides complementary presentation relevant operations Southern Hemisphere.