The Accelerator Neutrino Neutron Interaction Experiment (ANNIE) has completed Phase I background measurements partially funded under the Intermediate Neutrino Program and now seeks support to proceed to the Phase II physics measurement. Located in the Fermilab Booster Neutrino Beam (BNB), the experiment has two goals: (1) perform a measurement of the production of neutrons from nuμ interactions as a function of Q2 to constrain neutrino-nucleus interaction models, and (2) demonstrate the power of new fast-timing, position-sensitive detectors by making the first deployment of Large Area Picosecond Photo-Detectors (LAPPDs) in a physics experiment. LAPPDs are in commercialization and on track to be available on the timescale of the ANNIE physics phase. This proposal reiterates the physics motivation behind ANNIE and presents the results of Phase I. These results show that the neutron backgrounds are sufficiently low to immediately proceed to Phase II. Simulations of Phase II sensitivity are presented along with the plan to realize the necessary Phase II detector upgrades.