Each VAP can support a number of bound or metastable states corresponding to low-frequency vibrations of the complex. The latter are mostly Feshbach resonances; each of the vibrationally excited HF levels has sufficient energy to dissociate but the strong vibrational adiabaticity, owing to the high frequency of HF which can only weakly couple to the dissociation coordinate, causing them to decay slowly. We thus attribute peaks a-j and k-o to transitions to Feshbach resonances supported by the VAPs for vHF = 2 and 3, respectively. These Feshbach resonances are also consistent with experimental evidence of vibrational excitation in the HF product for the F + NH3 reaction. As the energy increases further, the representative wavefunctions for features q-t spread to both the PC and RC channels, as shown in Fig. . While this delocalization obscures some of the structure, the wavefunctions are dominated by four nodes in HF and thus are tentatively assigned as arising from HF (vHF = 4), owing in part to the VAP here becoming less well defined due to its proximity to the TS. Unlike the wavefunctions for the preceding features, these include a large component that is delocalized in the RC channel, as displayed in Fig. . Such wavefunctions are thus qualitatively different from the product channel Feshbach resonances at lower energies discussed above and represent a key observation of this work. The spacing of these features and their widths are considerably tighter than those involving HF (vHF = 3), with an average spacing of 275 cm -1 (compared to 775 cm -1 in vHF = 3). As discussed in the SI, these features are tentatively attributed to excitations in the pseudo-rotational mode of NH3 in the F-NH3 complex.